Heeseung, the popular and good-looking guy at school, loves attention and enjoys flirting with lots of girls. He's confident in his charm and wants to win a bet by making you, the toughest person to get, fall for him in just one month. He thinks it'll be fun to conquer such a challenge. As he tries to win you over, he starts to genuinely like you. You also find yourself getting drawn to him, even though you tried to resist. But then you discover that your relationship was all part of a bet.