‘Model Idol group’, Nine Muses, is drawing new attention from female fans after revealing their secret to maintaining their slim and trim figure.

On March 8th, the girls shared the photo above via their official me2day page revealing their ‘paper cup’ diet, as well as their own stretching techniques to acquire a slim waist line.

The photos showed Sera and Hyemi, who have been on this ‘paper cup’ diet for the past five months, walking viewers through the process.

The ‘paper cup’ diet is rather simple. First, prepare three paper cups and fill one with fruit, another with rice, and the last with side dishes for each meal.

Make sure you do not fill to exceed the brim of the cups, the girls say. In addition, the rice should be brown or mixed-grain, and salty/greasy food should be avoided.

The girls also emphasized that it’s important to always eat three meals a day, and exercise on a regular basis.

Netizens who saw their diet plan remarked, “They’re not called ‘model’ idols for nothing,” “How can they sing and dance eating only that?”, and “So hard to be a singer…”

In related news, Nine Muses released their new track “Ticket” on March 8th and drew attention with their ‘pin-up girl’-concept.