Refers to a (usually exaggerated) swelling on the head caused by minor trauma injury to it. Most frequently used for comedic effect, either to make depictions of [[tsundere|physical violence in light-hearted material]] more palatable, or to indicate a character has been punished for some action without having to actually depict the punishment. They seldom last longer than one scene, and virtually never represent serious injuries.

Frequently appears in conjunction with [[crossed bandaids]]. If someone is bumping their head against another person's head, use [[headbutt]] instead.
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