An 80yo lady is talking to her 30yo cat and lamenting about how she's not sure who will outlive the other. The cat suddenly talks to her and says that will be a problem. MC is surprised and the cat says if they live to 30yo they become a Nekomata and gain powers. So the cat says they can make her younger to take care of them, but only 2hrs a day bc they're a new nekomata. After she has sex with the neighbors she notices she didn't change back and the cat says that if she gets finished inside she will stay young for an entire day. Later she gets finished inside twice in one day and notices she seems a bit younger than previously. The cat comments that if she takes in cum too often she will get younger, so keep it to only once a day. Predictably things get out of control and they cum inside her multiple times, so she wakes up the next day as like 5 years old or something. To which the cat then has to take care of her for the day instead (The cat can shapeshift into the MC as well). The cat goes to teach them a lesson, but the fat otaku turns the tables on her and the last scene is the MC feeding the cat and her commenting that they should avoid getting involved with the fat otaku from now on bc he's too much trouble to handle.