Osomatsu-kun: Back to the Me no Deppa no Maki

Osomatsu-kun is a Japanese manga that was created by Fujio Akatsuka that ran from 1962 to 1969 that follows a batch of sextuplets and the shenanigans they get themselves and others into. While it was followed by a 1966 TV show, its true claim to fame was thanks to a colorized 1988 TV version that focused more on breakout characters Iyami and Chibita. The series outside of Japan is arguably known for its older, wiser, cruder, and more modern follow-up, Osomatsu-san, a.k.a. Mr. Osomatsu.

You are Osomatsu, the oldest of said sextuplets. One day, local conman Iyami summons you to solves the mystery of Iyami's signature buckteeth and the time paradox surrounding it. Thanks to Dekapan's and Chibita's help, Osomatsu goes back in forth in time to set things right! The title roughly translates to "Young Osomatsu: Back to the History of Me (Iyami, as he refers to himself) Overbite, a pun on Back to the Future since time travel is involved.