Doujinshi with title Musuko no Tomodachi (← Incubus) ni Miryou Sareta YanMama wa Mesu ni Naru and alternative title A Young Mother Gets Charmed by Her Son's (Incubus →) Friend and Becomes His Bitch | 息子の友達（←インキュバス）に魅了されたヤンママはメスになる