Su-hyeon is dating his university senior, Ji-ho, but somehow still feels lonely. Ha-neul, a third-year highschooler who has an unrequited love for Su-hyeon, is always eagerly awaiting his tutoring time with Su-hyeon.

One day Ha-neul confesses to Su-hyeon but is rejected since Su-hyeon can only see him as a cute student and little brother. The two of them go back to their everyday lives but as time goes on, Su-hyeon who is stuck in his tough everyday life, and his former student Ha-neul are reunited in a department office he is visiting…