The actor took on a role of a guy friend who's been having a crush on an extremely lucky girl for 3 years. He's so caring that he goes to pick her up and even takes her home after receiving drunk texts (yeah, drunk texts. She obviously likes him too).
At the end, he makes the move and confesses his love for her. Happy ending and major shim koong. Go ahead, and treat yourself with Park Bo Gum's sweetness.