Katekyo Hitman Reborn!

Tsunayoshi Sawada, or No-Good Tsuna, fails at almost everything- ball sports, tests, quizzes, even crushes. But when he gets a home tutor, this is where Tsuna's life begins to take a different course. His home tutor is Reborn, an infant hitman from the Mafia from Italy who uses spartan ways of teaching Tsuna various things.