Just after the commotion caused by the appearance of Jin-hong's parents, Eun-mi and Jin-hee experience their first family loss when Mi-jung and Eun-mi's mother passes away. They might not have shared blood, but she was Eun-mi's mother and Jin-hee's grandmother. Jin-hee, who becomes restless, starts to contemplate being independent. Can Eun-mi and Jin-hee, who have never been apart, be able to go their separate ways?

Jin-hee and Jin-hong take utmost care of Eun-mi following the attack, which brings the three of them closer. Meanwhile, Jin-hong's parents suddenly appears and encourages Jin-hong to marry Eun-mi, believing it would be a better choice for Jin-hee. However, this family seems to have differences at every turn. Is this marriage really a good idea?

A real culprit may be after Eun-mi. Despite opposition from the main office, Jin-hee and Jae-won accelerates their investigation into the culprit. The team members, who have become close after solving the single-parent assault case, also help Jin-hee in their own ways. Jin-hee secretly continues her investigation for Eun-mi's sake, only to find herself hiding more. Meanwhile, it seems that someone is constantly watching this mother and daughter duo...

Eun-mi encounters Ji-eun, the bully of her school days and Jin-hong's younger brother, and a strange war of nerves ensues. Eun-mi draws a line at Ji-eun telling her not to take an interest in Jin-hee. Meanwhile, Jin-hee suspects that there is another culprit who attacked her mother and asks Jin-hong to help ensure Eun-mi's safety. In front of Jin-hee, who seems to have opened up a little to Jin-hong, a maternal aunt... or maybe a paternal aunt appears.

Eun-mi is attacked by a man in a baseball cap while walking at night. Jin-hee belatedly gets a call from Jae-won and rushes to the police station where Eun-mi is. Seeing Eun-mi in a mess, Jin-hee hates herself for not being able to protect her mother. But she becomes more resentful toward Jin-hong, who promised that he will protect Eun-mi.

Jin-hee planned a mother-daughter trip to make up with Eun-mi, but nothing seems to go her way when Jin-hong suddenly shows up and disrupts her plans. On the trip, Jin-hong keeps on tiptoeing between the uncomfortable Jin-hee and unreadable Eun-mi.

Jin-hee is shocked by Eun-mi's revelation. When she was a child, Jin-hee didn't meddle on her mother's relationships, afraid that she would be like a poop that's attached to a goldfish, but now, she tells her mother not to meet with Jin-hong. Eun-mi, on the other hand, continues to meet him!

A man keeps on following Eun-mi. After the recent murder case, Jin-hee becomes anxious and tries not to leave Eun-mi alone, but she is worried because a strange man, Park Jin-hong, keeps wandering around their apartment. Meanwhile, Jin-hong stops by the orthopedic clinic for a treatment.

Jin-hee tries to adapt to the Namchon Police Station, but it doesn't go her way. After their first get-together, Jin-hee accompanies a drunk Jae-won home, and they talk about something unexpected. Meanwhile, a suspicious person is seen around the woman Eun-mi saved.

While examining Mrs. Na, a patient who came to the orthopedic clinic, Eun-mi sees bruises at her back and tells Jin-hee that she suspects domestic violence. They also suspect that Mrs. Na's grandson was also abused. Eun-mi, who hates people who hit their family, gets angry again.

While doing her first patrol for the Namchon Police Station, Jin-hee hears a report of a burglary at their house, and Eun-mi manages to catch the culprit. However, upon hearing the reason for the theft and that the culprit will not be detained since it's his first offense, Eun-mi, the "neighborhood crazy bitch," takes matters into her own hands.

An immature mother, Eun-mi, and her daughter, Jin-hee, live their daily lives like sisters. Jin-hee works at the Wolsan Police Station, and due to an incident, she is unjustly demoted to calm public opinion. Jin-hee goes home looking forward to drinking cold beer with her mother, but she sees something she had never imagined.