Izumi Kōshirō

Profile
Koushiro is a computer expert and spends most of his free time researching on his laptop (which resembles a Tangerine Apple iBook, only with a pineapple symbol). He is very curious and is always making theories and trying to understand the world around him. He starts out as a very introverted person, who isn't very in touch with other people and doesn't really understand their feelings. Being logical and thoughtful, he doesn't appreciate impulsiveness and gets angry when people around him act before thinking. He used to be on the soccer team with Takenouchi Sora and Yagami Taichi, though this was only to avoid contact with people as he isn't that good at playing soccer. He is the partner of Tentomon and the bearer of the Crest of Knowledge

Koushiro's biological parents died in a car crash when he was a baby, and he was adopted by a distant cousin of his father's. He was unaware for most of his life, and once he found out, he was devastated. However, he had since learned to accept himself as a true Izumi.

Prelude to Digimon Adventure
When Koushiro was young, he lived in Hikarigaoka with his parents. On March 1995, he witnessed the fight between Greymon and Parrotmon. After this, his family moved to Odaiba.

Sometime before Digimon Adventure begun, Koushiro overheard his parents talking about whether they should tell him he is adopted or not. He took this hard, believing he is not a true Izumi and thus a disgrace, and started to subconsciously distance himself from people, especially his parents.

Digimon Adventure
Koushiro was the brains of the group, and he frequently helped the group out of difficult situations. He became the owner of the Crest of Knowledge, not because he was extremely smart (which he was), but because he also had a hunger for the truth.

At one point, when Koushiro and his parents were hiding away during the siege on Odaiba, Koushiro confronted his parents on the subject of his adoption. They revealed to him that his parents died in a car crash when he was a baby and Koushiro's adoptive father, a distant cousin of Koushiro's real father, adopted the orphan as his own. After learning this, Koushiro accepted his past and truly accepted his adoptive parents as his own.

Digimon Adventure: Our War Game
In Our War Game, Koushiro was the one who first discovered a DigiTama infected with a computer virus on the Internet. He rushed off to alert the others, at first only successful in finding Taichi. He played a key role as the brains behind the attacks that were implemented by Taichi and Yamato.

Between Digimon Adventure and Digimon Adventure 02
In May 2000, Koushiro arrived at the Digital World and gave up his Crest power to free the Four Holy Beasts. As a result, Tentomon lost the power to evolve to Perfect.

Digimon Adventure 02
Although he grew, he was still short compared to the other Chosen Children. Koushiro had a lot of free time comparing to some of the other old Chosen, and often stopped by the Odaiba Elementary computer club to help the new Chosen Children. He was still very much into computers, and was curious about the new items the new Chosen had access to. According to Inoue Miyako, he was somewhat revered as the former president of the school's computer club.

Digimon Adventure 02: Diablomon Strikes Back
Like in Our War Game, Koushiro was responsible for the planning and execution of the attacks on Diablomon. He was the one who gathered all the Chosen Children (including Tachikawa Mimi who flew in from America) to help defeat Diablomon and stop the havoc it wreaked on the net and the real world.

25 Years Later
By the year 2027, Koushiro set up a research team to study more of the Digital World than what the human population already knows. He works with Takenouchi Haruhiko, Sora's father, and Kido Shuu, Jou's older brother. He is married and has a daughter, who has a Motimon as her partner.