"Come on! No need to be shy!" Matsumoto cried, yanking firmly on his uniform. "It's nothing I haven't seen before!" Gin/Rangiku, takes place before the Soul Society Arc.

Tsuna and his friends found a wounded white haired boy on their way home from the snow fight. They found that the boy lost his memories and let him joins Vongola to help him remember. What will come with this boy's arrival in mafia world?