Tsukkomi

This character reacts like a tsukkomi.

In a Japanese comedy duo, the tsukkomi (突っ込み) refers to the role one comedian plays in "butting in" and correcting the errors of the other (called the boke). It is common for tsukkomi to berate boke and hit them on the head with a swift smack; traditionally, tsukkomi often carried a fan as a multi-purpose prop, one of the uses for which was to hit the boke with. Boke and tsukkomi are loosely equivalent to the roles of "funny man" or "comic" (boke) and "straight man" (tsukkomi) in the comedy duos of western culture.

In stories, tsukkomi refers to a typically level-headed character who habitually engages in no-nonsense critical commentary on the behavior of funny characters.