Yukio Oikawa is a character in the anime series Digimon.
Oikawa is considered by many to be the most tragic character in the series. He is one of the few human adults to have a knowledge of the Digital World. He was born in 1969. As a kid, he was an extreme loner; mocked and shunned by classmates, he had no friends. A boy named Hiroki Hida was the only one who never treated him like dirt and became his only friend; Hiroki was born in the same year as Oikawa.
Hida had this obessesion: he could communicate with the Digital World through old video games and he shared the same obessession with Oikawa. They both ended up communicating with the Digital World. They spent hours and hours on the video games talking with the Digital World. Eventually, Oikawa met his own Digimon named Datirimon Pipimon.
Hiroki's father, Chikara, became very worried about the obsession his son had so he decided that Hiroki and Oikawa were being too childish. Chikara forbid his son from playing video games and tried to separate Hiroki from Oikawa, fearing that they were spending too much time together. The two were heartborken but they remained friends; they made the promise to each other that, one day, these two would go to the Digital World and they started sharing their dreams and never told anyone else about it. Oikawa worked with Ken Ichijouji's father as a computer programmer.
In 1995, when the Hikarigota incident occurred, Oikawa went to ivestigate; he worked along with Nancy Takaishi (Natsuko Takaishi in Japan). There, Oikawa learned that Hikarigota served as a gateway to the Digital World. Four years later, on August 3, 1999, Oikawa visited the grave of the recently dead Hiroki, angry that Hiroki "broke" his promise. Oikawa then saw the DigiDestined in the sky as they leave Odaiba. Seeing his dream realized, Oikawa was soon possesed by the disembodied spirit of Myotismon...