Lookism

For his entire 17 years, Park Hyung Suk has been at the bottom rung of the school hierarchy, constantly endured ridicule from his peers due to his short, overweight, and unappealing appearance. Seeking a respite from his primary bully, Lee Tae Sung, he moves to Jae Won High School in Seoul, a vocational school with a reputation for its relaxed, liberal approach to education.
However, just days before his enrollment, Hyung Suk wakes up to discover that he no longer has his former physique but instead now has a perfect body – tall, handsome, and toned. As much as he enjoys his new appearance and popularity at J High, his former body still exists beside him, and he switches between them almost every time one falls asleep.
Adapting to his significantly different lives in each body, Hyung Suk must also investigate the origins of his new, nearly superhuman body.