Both are 22 years old.

Although Kunikida is a serious individual that only follows his ideals, he is shown to be naive at times, especially when he is with Dazai. He is calm, careful, serious, and easily irritated, having exasperated outbursts, which are primarily caused by his partner, Osamu Dazai.

Dazai has mysteriousness, self-destructiveness, intensity, and an enigmatic nature. Never revealing his plans until later on, and is extremely smart.