Main story of the Beware of Reborn Trilogy Summary: When Tsuna was young he met Reborn in Italy while a mission as Cielo. He warmed Reborn's cold heart until he he left when his mission ended with a promise that they will meet again. For 7 years Reborn yearned for Tsuna's warmth again until he got a mission to tutor the Decimo. Reunited they promised to never lose each other again, and Reborn intends to keep that promise.