Shouma is a cool and friendly guy. He has a very close and playful relationship with Keiki and is good at giving advice about girls. He is popular with girls throughout the school however he is not interested in any of them.

Spoiler

He is only interested in Lolitas (lolis) and he describes himself as a practitioner of the way of the Lolita.

Spoiler

It is shown that he has turned into a lolicon due to a traumatic experience with his older twin sisters, Yuuhi and Asahi, who painted chocolate on their bodies before surprising him on Valentine's Day. This combined with their constant playing around with him caused him to avoid girls older than him (with the exception of Koharu, who he later starts going out with), turning him into a lolicon.

(Source: Kawaikereba Wiki)