Birthdate: July 22, 1962
Blood type: O
- 1987: Waseda University School of Economics & Political Science
- Tokyo Metropolitan Musashi Senior High School
- Agi Tadashi, shared with his older sister, Yuko Kibayashi (樹林ゆう子), non-fiction writer.
- Seimaru Amagi (天樹征丸)
- Yuma Ando (安童夕馬)
- Yuya Aoki (青樹佑夜)
- Joji Arimori (有森丈時)
- Hiroaki Igano (伊賀大晃)
- Ryo Ryumon (龍門諒)
Received the Kodansha Manga Award for Shounen in 1995 (The Kindaichi Case Files) and in 2003 (Kunimitsu no Matsuri).