So figure is very important for female stars, especially for the female love beans in the group. Because they often sing or dance and wear skirts, if they are in poor shape or slightly fat, they will not be photographed in skirts.
The second reason is the requirements of brokers. Korean agents are cruel to female stars and restrict their diet and exercise, so many agents don't allow actresses to eat sweets or eat too much.
Therefore, it is often seen that many female stars have boiled vegetables or some low-calorie fruits for dinner. So they just want to look good in front of the camera.
The third reason is that Korean fans are extreme. If female stars gain weight, many fans will personally attack them. Even some black powder words are hard to hear, and many stars can't stand such abusive ways, so in order to avoid personal attacks, female stars will deliberately maintain their bodies.