A lewd instructor's erotic ass ejaculation control

There is a fitness gym that is well known for being able to get the body you're aiming for if you join... Reiko, who works as an instructor at a seemingly ordinary gym, uses secret membership management methods to stoically alter her body. The method was to feed the members on their sleek butts and give them a "reward" of ejaculation only to those who have achieved results by wearing chastity belts. Every day, members dream of ejaculation and continue to train at the gym...