Masashi is Hiroyuki's best friend. He is very peaceful, with an air of quiet optimism. Whenever there's any sort of argument or ruckus, Masashi is usually the cool head that calms everyone down and gets them back on track.
You might not expect it from such an easygoing, soft-spoken guy, but Masashi is actually quite good at sports, and is always busy with club activities.
(Source: RightStuf)