Haruka Nanase, often called Haru, is the main protagonist of the series. His demeanor is cold and distant, even towards people that he's close to. He seems disconnected from almost any situation he's in. He's very aloof and passive about conflict and usually bottles his emotions up until it blows up in his face. However, if you look deep down, you'd be able to see that he genuinely cares about his friends. On the surface, it seems as if he only cares about swimming, though that is held in very high regard. He'd never pursue it competitively, however.

Haru's voice is mid to mid-low. It's soft with a sort of indifferent tone. He does emote when things get serious, so do keep this in mind.