My childhood friend—and also my first love—Oto suddenly appeared before me. Seeing her exhausted and asleep, I couldn't suppress my overwhelming desire. Sensing my lust, Oto began comforting me. After that, we started an odd cohabitation. But then, Oto told me she wanted to become my pet. To fulfill her fetish, I put a collar on her, and gradually became addicted to her depraved acts.