17 year old exemplary student Bae Sugu lives alone with his father, the vice principal of his school. Weighed down by his father's expectations, Sugu has to hide his one true passion: swimsuits. He does not know where it comes from, but his passion is pure and genuine - and often misunderstood. But one day, when Sugu is secretly taking pictures of swimsuits by the pool, he is caught by his homeroom teacher who forces him into something ridiculous. Can Sugu find something to get out of the standstill his life has come to? Can his heart beat again?