Quantum Mistake.

체인지가이

Quantum Mistake, originally titled Change Guy (Korean: 체인지가이) after its Korean-language title, is a manhwa originally published in 31 volumes between 1998 and 2006. It was authored by Son Eun-ho and illustrated by Choi Myung-su. It tells the tale of two boys, Woo-Soo Choi and Kang-Too Jee, after their souls are accidentally switched into one another's bodies.