Who Do You Think is Ishiyama's Strongest?

is episode 21 of the Beelzebub anime.

Summary
Furuichi is woken up by Alaindelon at 4:00 A.M. and is teleported to Ishiyama High to watch Oga and Tojo's fight with Hilda, Lamia, and Forcas Rachmaninoff. Meanwhile, Kanzaki, Himekawa, and Shiroyama confront Aizawa and Karou and begin to fight, but are quickly beaten by them, but they refuse to give up because of their stubborness. Natsume shows up and defeats Karou in one blow, and is about to deal with Aizawa. Kunieda and the Red Tails finish dealing with the delinquents and go to watch Oga and Tojo's fight, with Oga at a disadvantage. Beelzebub activates the Zebul Spell, thinking Oga can't can't win, shocking everyone. Lamia accidentally sets off one remaining firework and it's aimed at Oga and Tojo. Oga easily stops the firework and causes a giant flaming Zebul Spell to appear on the ground. Oga orders Beelzebub to not interfere in his fight, promising he will win and Beelzebub erases the Zebul Spell. Oga and Tojo resume their fight, which goes on until dawn, and just as it looks like Tojo is about to win, Oga spins around and performs a suplex on Tojo, winning the fight. Oga tells Beelzebub he won the fight and Beelzebub tackles Oga to the ground. Tojo's past is revealed, showing a man he looked up to who taught Tojo the ture meaning of fighting and had a Zebul Spell on his shoulder, which Tojo got tattooed on his shoulder in order to look like him, and Tojo tells Oga he is now the strongest at Ishiyama High.

Next episode preview
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.