Warship Boy.

Kaisei Sakamoto is a 16 year old boy who is inclined to settle everything with his fists. He grew up in a town where you can see both Nagazaki and Gunkanjima, living with his father. His father, Genkai Sakamoto, runs a small ramen shop. The father-son duo has just recently had a large fight. The story showcases fragments of one's youth and the questions that crop up while growing up.