Supyeongnaka

Han-Joo Yeo, a reserved and introverted student, has been hopelessly in love with the most popular guy in college, Chan-Young Choi. Despite the unrequited love and constant feelings of regret and humiliation, Han-Joo finds himself unable to end the relationship. But when his father remarries and introduces a stepbrother, Ji-Hyun Yoo, into the mix, strange things start to happen. Nobody seems to notice the tall and handsome stepbrother, and soon, things begin to take an unexpected turn.
(Source: Tapas)