Jaehee, an international student hit with academic probation and a breakup at the same time, picks up a suspicious self-improvement book in his quest to become a better man.

The first person to notice Jaehee's transformation is Miles, who is busy putting on a "hot guy" persona. Wanting to be just like Jaehee, Miles buys the very same book. Even though he struggles to read it because it's in Korean, he figures it's a small price to pay if it means becoming a man like Jaehee.

However, the book wasn't meant for self-development—it wanted "body development"—and before they know it, the two cross a line of no return...