Ore Isekai de Mahoutsukai ni Naru

Sasuke Sayama, loner, pervert, and... magician? After being transported to another world through his bathtub, he meets Aina and Elisa, two warrior princesses loyal only to their kingdom. But how long will that loyalty last when faced with pleasure? Tricking them into signing a "magical contract", Sasuke casts "lewd crests" upon them, breaking their minds and quickly converting their loyalty from their kingdom, to his cock.