It asks a question most battle anime ignore: What happens to the hero when the system that always saved him breaks?
When Oga finally stands up, his dialogue is haunting: "I got bored. Bored of winning. But you… you’re boring in a different way. You’re boring because you made me feel like I’d already lost." Beelzebub Episode 54
Except, Episode 54 doesn't roll credits. It rolls a funeral march. Fuji Kageyama isn’t a joke. He doesn’t monologue. He doesn’t posture. He simply executes. His power, "Darkness," isn’t flashy—it is absolute negation. When he attacks, he doesn’t knock you out; he erases your will to fight. It asks a question most battle anime ignore: