Freestyle swimmer (crawl) of the Iwatobi High School swimming team.

Haruka Nanase (Haru) is an 11th grader who loves to swim. His strong and quiet swimming style fascinates many (as quoted by Nagisa Hazuki, "He reminds me of a dolphin."), and he holds a strong fixation on freestyle swimming.

His best friends include Makoto Tachibana & Nagisa Hazuki from Grade School, then he later befriends Rei Ryugazaki. He used to be best friends with Rin Matsuoka, but now Rin has become Haru's rival. Haru has created the Iwatobi High School Swimming Club along with his other friends to take down Rin.