Yadorimushi ~Boku ga Shokushu de Shokushu ga Boku de~

A quiet protagonist, long the victim of bullying, stumbles upon a fallen tentacle seed. The next day, the demon girl Lilim visits him, inadvertently causing the seed to fuse with his body. To be free of this parasitic tentacle, he must assault women to gather enough energy for a new seed to emerge...