The male protagonist took his beloved pet fish out with a couple on Valentine's Day. After being laughed at and quarreling, he went home and made a wish to his fish, hoping that the fish would become his girlfriend. The next day, I found that the fish was missing, and a woman wearing the same color clothes as the pet fish was lying next to me. The woman said that she was the boy's lover today and could do one thing that any couple would do. The boy fantasized about many situations, but because he could only do one thing, he still chose to take off his pants and have sex.