Na-yeong is studying to be able to find a job. Studying alone is not easy but she still spends time alone. When she found out that her friend Ji-hee's grades have improved a lot while studying, she seduced her friend Yeong-bin and took off her clothes, asking him to join her. But Ji-hee's studying was different than I thought. A study forced to have sex. Na-yeong meets Min-soo in a new study and quickly starts to adapt to a new study. Will their unique classes end well? The delicious and bitter story of two different men and women just begins..