Natsu Sawada is a fictional character from the anime and manga series 'Katekyou Hitman Reborn!'. He is the pet box animal of Tsunayoshi Sawada, the series' main protagonist. Natsu is a small, lion-like creature with a playful and loyal personality, often seen by Tsuna's side. Despite his cute appearance, Natsu possesses strong combat abilities and aids Tsuna in battles, especially with his Synchronization ability, making him an essential ally and symbol of Tsuna’s growth as the Vongola Decimo.