Caregiver Mitsuki is tending to an elderly man named Hamura, who bears a striking resemblance to her late grandfather. Gentle and kind-hearted, Mitsuki gradually forms a deep bond with Hamura through her daily care routines. However, Hamura begins to develop unnatural feelings toward her. On the day he turns eighty, after Mitsuki carefully assists him with feeding and gives him a massage, Hamura can no longer suppress his overwhelming sexual desires and lets them erupt. Faced with an innocent, sexually inexperienced old man, Mitsuki has no choice but to perform sexual relief for him—an act that hints at unexpected developments to come.