Who Do You Think is Ishiyama's Strongest?

is episode 21 of the Beelzebub anime.

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Kunieda notes to Oga his accomplishment of taking over Ishiyama High. Oga claims their battle has only just begun and that he needs to undergo special training. Hearing Beelzebub's excitement, Oga is enthused and tells Beelzebub they'll spread honey on a chestnut tree and hide in ambush, that is, to catch a stag beetle as Kunieda notices. After Oga introduces the next episode, she becomes surprised to realize they may be training at a temple her grandfather knows.