Nenji Nagihara

Nenji is Nanaka's classmate and childhood friend. He is a delinquent, but after Nanaka's accident, he calms down. Nanaka's father entreats him to keep Nanaka's accident secret from other people. Nenji is occasionally referred to as 'Wild Hair Nenji' by some of the other characters. He has long, spiky hair reminiscent of certain stylized Shōnen anime characters.

(Source: Wikipedia)