When female college students armed with summoning books chant spells in the nighttime classroom... what appears is an old man incubus!? The girls, furious at the incubus who doesn't look like the handsome one from the smartphone game, have their spirits crushed. However, the old man incubus can't just return to the demon realm without doing anything since he was summoned. So, he uses his demonic charm and incredible technique to make the girls around him climax repeatedly! The invincible demon cock that shoots endlessly can't be stopped by anyone!