The handsome devil I met on the stairs

Tired of studying at the academy, Yeo-ju sits on the academy steps for a moment, playing on her phone. She encounters Tae-hyung, walking downstairs. Yeo-ju is afraid that Tae-hyung will find out she's on her phone. But Tae-hyung, being the devil himself, needs someone to deal with, so he decides to make Yeo-ju his deal...