Megami Taisen

Our hero was just an ordinary high school student. He finds a strange package addressed to him. He opens it and inside he finds a...melon? Seeing that he loves melons, he ate it quickly enough. Soon thereafter, he felt his body stiffen as he began traveling through space. He's caught by a beautiful black-winged woman. She tells him that he has eaten the "eroero fruit", and that's what brought him to her world. It also turns out that this woman, along with several others, is a goddess. What's an ordinary guy to do with all these scantily clad deities?