a "simple task" the title said.... LMAO
and novel readers, tell me why the priest MC is still obeying the church ? he said he's not religious, and with his strength, i think he can do whatever he wants.
so i suppose this has the same twist as "mahouka koukou no rettousei", where the MC is a powerful being but hide/seal his power, and that has something to do with the MC's little sister.