Anger, injustice, contempt, and a sense of loss— Seonwoo Ji-hoon experiences various emotions that he wants to draw out from Lee Hae-in. However, the only thing that Ji-hoon can offer to Hae-in, with whom he fell in love at first sight, is love. When Hae-in couldn't take his eyes off Ji-hoon's smile, which both devours and weakens him as his soon-to-be stepbrother, he realized that this one-sided love would lead him into a swamp.