Oikawa and Iwaizumi have been best friends since childhood, Oikawa dubbing the latter "Iwa-chan". Due to knowing him so long, Iwaizumi is one of the few who. Hajime Iwaizumi (Japanese: 岩泉一 Iwaizumi Hajime) is a third-year student from Aobajōsai High; he. 1 - 20 of Works in Iwaizumi Hajime/Oikawa Tooru .. This is a collection of Haikyuu angst requests from various friends, and I decided that I'd try to post.