But... we shouldn't do it. As Jin-goo's father suddenly leaves for England for a business trip, he stays in the same house with his stepmother, Ae-ran, who is still in an awkward relationship with him, but it is also uncomfortable to meet him at every meal. Ae-ran tries to take care of her son Jin-goo even if she's busy living every day as an English teacher and working part-time as a private tutor. She sometimes goes to work at night as if she had a part-time job. Meanwhile, Jin-goo often goes to karaoke rooms to meet Woo-mi, who is popular, thanks to the introduction of his senior in the neighborhood. One day, when that senior came home for a drink and encounters a huge fact, he turns around, revealing a huge secret and revealing their mixed erotic romance.