A man summons Miyu, a novice succubus in training who intends to drain his soul through relentless pleasure. Despite her efforts to push him to a lethal limit, the man survives the encounter and finds himself hopelessly addicted to the dangerous demon's touch, desperate to summon her again.
A lonely man is repeatedly drained of his life force by Miyu, a young succubus who visits him nightly. While the man accepts his fate with a submissive desire for fulfillment, his profound loneliness and honesty unexpectedly touch Miyu's heart. This emotional connection leads Miyu to fall in love with him, triggering a transformation that turns her into a human and changes their relationship forever.
After deciding to care for a mysterious doll in his room, a college student finds his luck improving dramatically. The doll, Nina, eventually comes to life in human form to express her gratitude and love for him, leading to an encounter of insatiable sexual desire.
Shuu's life improves after he begins caring for a cursed doll, but the doll, Nina, manifests in human form to claim him for herself out of jealousy. After Shuu chooses Nina over his girlfriend, the two discover a hidden basement containing a letter from Nina's former owner. The letter reveals that Nina was not abandoned but was deeply loved by a girl who passed away from an illness, leading Shuu to promise that he will stay by Nina's side forever.