The sister who has absolutely no interest in her brother falls in love with his morning erection!? Deciding to keep her brother's morning erection as a pet, the sister comes every morning to nuzzle, kiss the glans, and use her vagina as a house to insert it! Although the brother acts coldly because he is seen as an obstacle, his morning erection is so adorable that she can't help but dote on it!! In the end, she even finds herself feeling like a pet, nuzzling her lower body while having cat ears! A triangular relationship of incest between brother and sister!