Uchi No Otouto Maji De Dekainn Access

"Uchi no Otouto, Maji de Dekain" is a Japanese light novel series written by Souichirou Shinuno and illustrated by Hiro. The series was later adapted into a manga and an anime film.

I think I have it!

The title roughly translates to "My Little Brother is Actually a Super Strong Ninja" or "My Younger Brother is Actually a Super Strong Ninja". uchi no otouto maji de dekainn