Katsuki (克樹)

Overview
Katsuki (克樹) is one of two playable characters in Mata, Itsuka. (また、いつか. ), the other being Shun (峻).

Appearance
Katsuki has short black hair. He wears a green T-shirt with a wide light-green horizontal stripe in the middle, light blue cropped pants and whitesports shoes.

Personality
Not much is known about Katsuki's personality.

Past
It is unclear what the relation between Katsuki and Shun is. Judging by the game's title, it could be that they were separated once and they wish to meet again sometime.

They could be brothers, judging by their similarity in appearance. They could be (childhood) friends who were set apart by life circumstances. This could be backed by the fact that you switch between them using the similar telephones in each of their rooms, suggesting that they are now connected by phone calls.

They even could be the same person given their similar in-game descriptions and having several effects in common. Katsuki and Shun could be representative of the same person at different stages of life.