Adopted into the Kaiba family as an orphan, Kaiba is at the helm of the world’s largest multinational gaming conglomerate, Kaiba Corp, serving as its majority owner and chief executive officer in addition to being the founding President and CEO of the private investment company KC Holdings . An intellectually gifted and innovative computer programmer, engineer, and inventor during his youth, he invented virtual software for playing video games as a young child prodigy. Nonetheless, an estranged relationship with his stepfather and outsmarting him auspiciously led the young Seto towards a seamless corporate takeover of KaibaCorp. With access to vast wealth, technological resources, and a wellspring of scientific and business expertise, Kaiba seeks to expand Kaiba Corp's business operations not just across Domino City but the entire world. A competitive businessman and cutthroat investor, Kaiba is feared throughout the business world; earning him the hospitality and respect that he needs from his peers and rivals.
Through his philanthropic hospitality and passion for Duel Monsters, Kaiba is also the owner of the Central Duel Academy, a private educational institution dedicated towards training the next generation of up and coming Duel Monsters players. A native of Domino City, Japan, Kaiba formerly sought to become the world's greatest player in Duel Monsters by defeat his arch-rival, Yugi Moto. Following the Pharaoh's return to the afterlife after regaining his memory, Kaiba returned to the private sector with the goal of expanding Kaiba Corp's business operations across the globe. At the same time, he married Ishizu Ishtar, a former Egyptian tombkeeper who currently serves as Secretary General of the Egyptian Supreme Council of Antiquities at the Domino City Museum.
Kaiba is often portrayed as a snobbish business tycoon with a condescending and conservative personality who shares a common contempt towards those he considers as inferior to him, whether socially, in the business world, or competitively towards a dueling opponent. He is slightly friendlier towards those he considers his competitive equals and more often than not as someone who softens up as the story goes on and less often than not as the villain of the story. He ends up in a relationship with Ishizu Ishtar.
In the two years since the Pharaoh left the living world, Kaiba and Mokuba are currently the only people left in Domino who know what happened due to everyone else either being in America or on vacation in China. Because of that, Kaiba's forced by Mokuba to welcome the Ishtars back to Japan when they arrive there.
Kaiba then ends up having a casual discussion of the Giver over dinner. Kaiba then offers to drop the Ishtars off at their hotel. The next day, Mokuba tricks Kaiba into going to one of his warehouses while Marik tricks Ishizu as well. After some talking, the two of them agree to go out just to see how it works. That night, Kaiba takes Ishizu to his yacht, and they spend the night talking about books they both like and have a good time. Kaiba then gives Ishizu his jacket when it begins to get cold when they go home, and Kaiba lets her keep it since he has many others.
After only a few days of dating, the relationship already starts to turn cold due to Kaiba's determination to always move forward, and his business decisions. After a few more dates, Kaiba begins to have feelings in Ishizu that he can't explain, and he has no idea if they have a future together. When they go for a walk, Ishizu asks Kaiba where the relationship is going and if money means more to him than love. Kaiba says that without wealth, love "grows dry and cold." Ishizu then leaves for the hotel she's staying at, and Kaiba goes home. Once he arrives, he regrets some of his answers to Ishizu's questions.
The night before Ishizu and her brothers would go back to Egypt, Kaiba was given a vision by his previous incarnate, Seto. The vision showed what his life would be like if he got together with Ishizu. He would be happily married to her, and they'd have two children, a fourteen-year-old son named Seth, and a three-year-old daughter named Isis. After helping Isis with a broken ankle, Kaiba determines that he wants and needs this life. When he wakes up, he rushes to the computer and checks to see when Ishizu's plane leaves. Kaiba just barely manages to catch Ishizu, and he tells Ishizu that he loves her. They then have their first kiss. A year later, the two of them decided to tie the knot and end up marrying each other. Another year later, Kaiba and Ishizu had their son, Seth. Their daughter Isis is born a decade later.
Three years after Seth was born, Yugi arrived to ask Kaiba for help, which he gave after learning that Yugi's children, Tag and Anzu, were kidnapped by Rex and Weevil, so he used his satellite to find them since he was able to move past his grudge against Yugi.
Eight years after helping Yugi find his children, Kaiba and Ishizu had Isis, and a further five years after that, Kaiba invited Yugi, Joey, Mai, and their children to the Tokyo Duel Monsters convention where he revealed an invention of Corin Fudo's, the Duel Runner. He then announced an exhibition duel between Corin and Yugi to test it out, which Yugi won.
The next day, Kaiba was told by Seth about Yugi and Tag being kidnapped, and he had Seth tell everyone at the convention to keep them alert.
Kaiba then watched Tag's duel with the kidnapper, Mel Tyrone, and clenched his fist at the duel's apparent outcome. After Tag won, Kaiba called the police on Mel for kidnapping and attempted murder.
My Sister's DuelistEdit
Kaiba later witnessed an ex-employee kidnap Isis. Kaiba later got a call from the kidnapper about where he was, and Kaiba then told Seth, who went off to confront him and save Isis. Seth then defeated the kidnapper, and he gained a new friend in Kira Draco. They then returned Isis to the Kaibas, and Kaiba thanked Seth, and Seth put the credit on the Blue-Eyes Shining Dragon Kaiba gave Seth for his sixteenth birthday.
Disappointed with the output of the graduates of the Duel Academy, Kaiba personally took it over and has all the students duel against his step-brother, Odion, who was made Head of Security at the Academy. Kaiba then promoted Johnny to Ra Yellow after he defeated Odion.
Birthday for TwoEdit
Kaiba later attended Tag and Anzu's seventeenth birthday.
Journey to the PastEdit
Kaiba later attended a party to celebrate Tag defeating Mel in a revenge scheme of his called Death-T. He then took a chance to jab at Joey's intelligence when Mai remarked at how Johnny inherited his father's smarts, which he snidely equated to an insult.
New Member of the FamilyEdit
Kaiba later learned that Tea was pregnant again.
Return of GozaburoEdit
Kaiba later dueled Yugi in the finals of the Teacher's Tournament and lost when his Blue-Eyes Ultimate Dragon was destroyed by Yugi's Horakhty. Kaiba didn't take it personally and simply dismissed the students until next year. Kaiba then assured Isis he was okay before reluctantly letting the rest of the gang return home on his jet with his and Yugi's families. Kaiba then lost control of the jet as it was pulled into a new Virtual Fortress and was shocked to find that they were held captive by Gozaburo. Kaiba was about to accept a challenge to duel Gozaburo before Seth accepted for him.
Grandfather vs. GrandsonEdit
During Seth's duel with Gozaburo, Kaiba advised Seth not to let Gozaburo discard his hand. He then explained Exodia Necross to Seth when he was summoned.
Prince of GamesEdit
Later, Tag challenged Gozaburo himself and sent him to the Shadow Realm. After that, Kaiba used the safety protocals for his Virtual World to escape thanks to Gozaburo's arrogance. He then headed home with the others.
Kaiba went to a general get together at the Game Shop. After Tag lost his video duel with Pegasus, Kaiba's soul was captured to force Tag and Seth to participate in the New Duelist Kingdom.
Still a stuck-up, arrogant jerk with only a soft spot for Mokuba; he too is a junior and is in the same first class as Atem much to his dislike. They shared lunch once in elementary school and Kaiba hates that "the geek squad" considers him as their friend. He hates annoying, clingy, hyperactive, crazy people and yet, ironically, his first girlfriend is Kisara, a girl who has Kaiba got a call from Atem while at the business meeting every quality that he hates, or at least Kisara pretends to be like that. After hearing how Atem's father died, Kaiba was inspired to pick up where he left off. Something in his virtual world technology went haywire to such a point that not only were Yugi's and Atem's minds switched but his and Mokuba's as well. While Mokuba goes to his school to fill in for him, he works on fixing the problem from his mansion where he receives news from Mokuba that the error in the virtual system was intentional and that it seems there's somebody who's trying to overthrow him. After finishing the plans to get the virtual reality system fixed and switch all minds to the correct bodies, and handing them to Mokuba, he discovers, through a short conversation with Kisara, that she's not the hyped-up girl that she appeared to be but was actually rather shy and quiet. He made a vow to do everything in his power to get her to show her true personality more often. His life was also recently saved by Kisara when she pushed him out of the way when a light was about to fall on him, and she damaged her ankle in the process. Kaiba returned the favor when he made sure Kisara got back to the limo first before going off to see who had ruined his date. Kaiba also helped Mahad and Atem figure out why Daiki wanted to take Mana to live with him when he went over the will and pointed out that whoever Mana's legal guardian is, her half of her mother's money will be controlled by him or her. He also shows Mahad that the will also says that Mana's supposed to be taken care of in the most convenient way possible. When Kisara got scared of the thunder, Kaiba let her sleep in his room where he got her to show her true side and they almost kissed before he passed out. When he went to Egypt, he left Mokuba, who sneaked on, on the surface in case something went wrong again at the excavation. He then heard that the Ishtars believe that Kaiba is the reincarnation of a High Priest in the Nameless Pharaoh's court, and his successor, believing that it's a bunch of crap. He then ended up having to duel his assistant Lector of the Big 5 when they kidnap Mokuba. Kaiba is nearly broken as Lector reveals how Kaiba took over KaibaCorp, by manipulating Mokuba into going to their step-father, Gozaburo, to take over KaibaCorp. After some encouragement from Atem, Kaiba won the duel and asked Mokuba's forgiveness, which he got.
After losing his parents at a young age, the servants spoiled Prince Seto rotten. During Christmas one day when he refused to let an old beggar woman take shelter in his castle, she revealed herself to be the Enchantress Ishizu and turned Seto into a mammalian monster. Ashamed of his monstrous form, Kaiba concealed himself in his castle with a magic mirror as his only way to see the outside world. A rose Ishizu offered him would serve as the time keeper of the spell. If Kaiba learned to love another and earn her love in return, the spell would be broken. If not, he'd be doomed to remain a beast for all time. After four years, he fell into despair and lost all hope since he figured no one could love a beast like him.
When an old man named Solomon was let into the castle to warm himself after ending up lost, Kaiba walked in and shouted about how the servants betrayed him by letting a stranger enter the castle. He then asked what Solomon was doing in the castle and noticed him starring at him. Kaiba then tossed Solomon into the dungeon for trespassing.
When Solomon's step-daughter, Kisara, arrived to save her step-father, Kaiba appeared and asked what she was doing there. Kisara then demanded that he release Solomon, but he refused. She then offered to take his place, and this startled Kaiba since he'd never heard of someone doing that before. He then agreed as long as Kisara promised to stay in the castle forever, which Kisara promised, and Kaiba agreed. He then immediately took Solomon and had a carriage take him back to the village he came from. When Kaiba walked back down, Joey suggested giving Kisara a more comfortable room which Kaiba just growled at. Kaiba changed his mind however after feeling sympathy for Kisara never seeing her father again without getting the chance to say good-bye. He then told Kisara that as the castle was her home now, she could go anywhere she wanted except the West Wing. After arriving at Kaiba's mother's old room and letting Kisara enter he told Kisara that she would join him for dinner, and it wasn't a request.
Later while Kisara didn't come down, Kaiba wasn't very confident that Kisara would care for him since she was so beautiful and he was essentially an anthropomorphic wolf. He then listened to Joey and Isis' advice about being gentle, suave and sincere when Tristan came in and reluctantly said that Kisara wasn't coming. Kaiba then ran up to Kisara's room and ordering her to come down, but Kisara refused again. Kaiba then requested that she'd come down, saying "please" for the first time in his life, but she still refused. Kaiba then ordered that if Kisara wouldn't eat with him, she wouldn't eat at all. He then went to his room and used the mirror to see what Kisara was doing in there, and she was talking to Serenity about how she didn't want to have anything to do with Kaiba. Kaiba then began to despair until he reminded himself about how he'd never given up before, so he decided to try and act like a gentleman.
Kaiba then managed to prepare a tray of food and was about to go in when he saw Kisara, Joey, and Tristan pass and heard Kisara remark that the only thing that would make the palace perfect would be if Kaiba wasn't there. Kaiba then slammed the tray onto the floor and went back to his room in the West Wing. When Kisara arrived and was about to touch the rose, Kaiba showed up and shouted at her to get out, and accidentally clawed at Kisara's arm. Kisara then ran away, and Kaiba mentally abused himself for losing his temper. He then decided to go after her and bring her back.
Kaiba then saved Kisara with the power of his three Blue-Eyes White Dragons combined into the Blue-Eyes Ultimate Dragon to scare and fight off the Silver Fangs and Flower Wolves that were attacking her, but not before one of the Silver Fangs bit Kaiba. He was then taken back home by Kisara. After another shouting match between Kaiba and Kisara, Kisara thanked Kaiba for saving her life and Kaiba apologized for attacking her and everything else as Kisara did the same, and they began to become friends.
Kaiba and Kisara then talked about their families, and Kaiba revealed that he wasn't that close to either of his parents. When Kaiba struggled to eat some soup with a spoon, Kisara suggested drinking directly out of the bowel. Kaiba then asked Joey what he should do, and Joey suggested giving Kisara the library, which he did. After that, Kisara tried to give him King Arthur to read since he never read it, but he refused and eventually admitted that he couldn't read very well since he only learned a little bit of it and fell out of practice after the spell was placed on him. Kaiba did agree to let Kisara read to him as a way to refresh his memory. Kaiba easily enjoyed the story as well as Kisara and imagined himself as Arthur as he pulled the sword Excalibur from the stone and anvil and told Kisara, "Told you so" after Kisara read the bit about Arthur becoming king. He and Kisara then connected when Kisara admitted that she knew what it was like to be different since everyone in the village considered her odd. Kaiba then admitted that King Arthur was a very good story after Kisara finished. Kaiba then agreed to have Kisara help him learn how to read by reading Romeo and Juliet.
With Kisara's help, Kaiba easily mastered reading, and a few days after Kaiba saved Kisara, they were enjoying a fine winter's day as Kisara helped Kaiba feed some birds and the two then got involved in a snow fight. After that, Kaiba gave Kisara his jacket as they walked inside from the cold.
The next day, Kaiba read The Adventures of Robin Hood to Kisara and told her his first name, Seto. After that, Kisara asked to have dinner with Kaiba, which he eagerly agreed to.
Kaiba then got dressed in his best outfit as Joey encouraged him. Kaiba and Kisara then had dinner, and when Kisara asked Kaiba to dance with her, he was encouraged to do it by Tristan and Joey. He then danced with her. After that, Kisara said how she wished to see her father, and Kaiba gave her his mirror, and when he heard from Kisara that her father was sick and possibly dying, Kaiba let Kisara go save him. She then left, and Kaiba gave up on having Kisara love him, but he loved her, and that was enough for him to be content with giving up, even if it wasn't enough to break the spell.
When Bakura's mob arrived at the castle, Joey asked Kaiba for help, but he was too emotionally broken to care.
Bakura then attacked Kaiba, but Kaiba didn't fight back until Kisara arrived. Then when Kaiba fought back, he used the Ultimate Dragon to destroy Bakura's Ka, Diabound. After this, he was about to throw Bakura off of the castle before he begged for his life. Kaiba then let Bakura live, but he told him to get out, he then climbed up to Kisara as she arrived at a balcony outside his room, but he was then stabbed by Bakura while Kaiba knocked Bakura away, and Bakura fell to his death.
Kaiba then died in Kisara's arms from blood loss as he said he was glad to see Kisara one more time. After Kisara confessed her love for Kaiba, he was turned back into his human form by Ishizu, and he and Kisara got married.
An explorer. Kaiba went on the voyage to the new world colony of Virginia, claiming he didn't want his shipmates to have all the fun. As Captain of the ship, Kaiba looked at the sky. When a storm came up, Kaiba assisted Mokuba in tying down a canon. When Mokuba is swept overboard, Kaiba swings on a line to Mokuba's aid. He managed to get Mokuba back to the boat with help from Bakura and Ryou, stating jokingly that he was sure they'd do the same thing for him. Kaiba then explained to Pegasus that Mokuba fell overboard, not liking Pegasus that much. Kaiba later told Mokuba to only worry about his fortune and leave savages to him, opening a bear barrel with his sword. On the crow's nest, Kaiba told Mokuba that he'd been to hundreds of new worlds and rhetorically asked what could possibly be new about the one they were going to.