B. Ichi
Manga
B. Ichi is a Japanese manga series written and illustrated by Atsushi Ohkubo. It was serialized in Enix's shōnen manga magazine Monthly Shōnen Gangan from October 2001 to May 2003, with its chapters collected in four tankōbon volumes. Set in the city of Toykyo, the series focuses on humans known as "Dokeshi", whose abilities to use more than 50% of their brain power allows them to unleash special powers, provided they meet one unique condition each day. For the Dokeshi Shotaro, his condition requires that he do one good deed daily to gain the powers of any animal by biting its bones. After Shotaro meets the traveler Mana, they begin a partnership and journey to find Emine, Shotaro's childhood friend.
Description from Wikipedia, available under CC BY-SA 4.0. May be shortened.