The class 3-E mafia student
This story takes place right after the manga and instead all the arcobaleno are adults. Reborn tells Tsuna that he hasn't done much training since the fight with Bermuda and decides to send Tsuna, his guardians, and himself to a parallel world as 'training.' When they arrive in the parallel world they are tasked with helping the students of class 3-E in saving the world from exploding on march 13.
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