嵐山甚八

Jinpachi is also a delinquent and Nenji's rival. He often fights with Nenji, but due to Nenji's recent maturity, he gets irritated with him. In one instance in the series when Jinpachi fought with Nenji, Nanaka stopped it in a surprising way that caused Jinpachi to fall in love with Nanaka.

(Source: Wikipedia)