Monchan

Monchan is mocking and confrontational, readily participating in Yokkun's attempts to humiliate Yutarou.

He shows little sensitivity toward Yutarou's failed ambitions and joins in insulting the bathhouse itself. The latter is particularly provocative because Yutarou remains protective of his family's business.

Monchan's characterization is intentionally grounded compared with the assassins surrounding the series. He is an ordinary bully whose antagonism comes from social humiliation rather than murder contracts or underworld politics.

Monchan has no established assassin training, supernatural power, or specialized weapon.

Nothing shown of him places his physical ability anywhere near that of a professional assassin.

His presence instead highlights the enormous difference between everyday aggression and the violence Sakamoto routinely encounters in the assassin world.

Monchan appears during the Sakamoto family's bathhouse outing alongside Yokkun.

The pair encounter Yutarou and begin ridiculing him for returning to his family's business after previously leaving with greater ambitions.

Their insults extend to the bathhouse, worsening Yutarou's embarrassment while he is simultaneously preoccupied with Sakamoto's bounty.

Sakamoto's presence ensures that the mundane confrontation does not escalate significantly, while Yutarou's secret assassination attempts create the episode's more dangerous conflict.

Yokkun is Monchan's companion during the bathhouse visit and joins him in harassing Yutarou.

Yutarou is an acquaintance whom Monchan mocks over his return to the family bathhouse.

Taro Sakamoto is present during the confrontation and quietly keeps the situation under control.