Amami Rantaro

Ultimate Adventurer
Amami lost his sisters around the world and embarked in an adventure to find them. Now his latest clue on where they are has told him to come to TFR.

Season 0
Apparently a prominent character in S0.

Season 1
Spoiler: They weren't there.

Season 7
Original Rantaro escaped into the vents, where he was promptly bonked by a metal ball accidentally set up by his newer self.