As Tsuna tries to leave for school, he is surprised to see Dino's men waiting outside his house again. When Dino asks what his men were doing there, all of them reply that they ended up there after taking a stroll, causing Tsuna to realize that Dino is loved by his men. Suddenly, Gokudera and Yamamoto arrive and the three leave for school. As they walk, Dino shows concern for Tsuna after seeing his family and devises a plan to test them with Reborn.
As the three walk to school, Tsuna and Gokudera talk about Dino and his family while Yamamoto listens, thinking that Dino owns a company named Mafia. Suddenly, a car arrives and Tsuna is tied up and carried off, leaving Gokudera and Yamamoto. Reborn arrives behind them and explains that Tsuna has been kidnapped by members of the Momokyokai Yakuza that control that area, causing Gokudera and Yamamoto to go after them. After the two leave, Dino arrives with his men and a tied up Tsuna. He apologizes to Tsuna and explains that he was just testing his family and that Momokyokai are just a made-up group. However, Reborn corrects him and tells the two that the Momokyokai is a real Yakuza group, causing Tsuna and Dino to go and rescue Gokudera and Yamamoto.
They arrive at the hideout and are surprised to see that Gokudera and Yamamoto already defeated the Yakuza and are interrogating them for Tsuna's whereabouts. Suddenly, the other members of the Yakuza arrive and Dino tries to negotiate with them. However, the group refuses forcing Dino to use his whip but ends up hurting Gokudera, Yamamoto and himself instead, since none of his men are there. The Yakuza laughs and charges towards Tsuna. Tsuna screams for help and it came in the shape of Reborn's Dying Will Bullet. As Tsuna, Gokudera and Yamamoto beat up the Yakuza. Dino's men arrive causing Dino's athletic abilities to awaken and help defeat the Yakuza.
Back at Tsuna's house, Dino compliments Gokudera and Yamamoto and leaves. As he leaves, Gokudera comments that he talks big and that he is petty. Tsuna tries to defend him but ends up wrong when Dino falls off the stairs again...
Note: Bold + Italicized = First Appearance