It is similar to the Western party game of hitting a piñata: players are given a bat or stick, blindfolded and spun around three times, then attempt to strike the watermelon. Whoever cracks the watermelon first wins and afterwards the remains of the watermelon are shared with all participants of the game. It usually takes place at the beach during the summertime.
It might also involve a pun involving Ibuki Suika of the Touhou series being hit on the head, somewhat based off a line in one of the games about going "Suika Bashing" when fighting her.
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