The Godless World of Onee-Chan

When the son of a cult leader is transported to a world without religion he must bring the god he despised with him to save the world! The first volume in an ongoing series (with a hit anime adaptation now on Crunchyroll) Working for God in a Godless World is an all-new take on the isekai genre! When Urabe is sacrificed by his father to the all-powerful Mitama, he prays that he can finally be without religion. He wakes up in a placid world free of faith, and begins a new life there, but when the truth is revealed, that the ruling empire purges the citizens, Urabe must find his faith and summon Mitama to protect them! 

(Source: Titan Manga)