At the beginning of episode 7 "The Penthouse: War in Life", the opening ceremony of Cheong A School, Ro Na was initially chosen to solo at the opening ceremony but due to an accident, she was late to attend, the position of Ro Na do Eun Byeol replace. Because she wanted to inherit the Cheong A school system from her father, Seo Jin tried to harm Ro Na so that her daughter, Eun Byeol, would take over from there to regain her father's trust.
But in addition to Ro Na, she had to eliminate Seok Kyun, then Eun Byeol could solo. Seo Jin also discovered that the twins were cheating in the competition, so she looked for Dan Tae to pressure, promising Dan Tae not to make a big deal if Seok Kyun pretended she couldn't sing by sick. Then as the art director of Cheong A School, Seo Jin reinstated the Cheong A art contest that was canceled due to her conflict and Yoon Hee 25 years earlier.
Suddenly Dan Tae announced the termination of the relationship with Seo Jin and showed interest in his wife, making her extremely angry. Seo Jin called Ro Na to reprimand her for not attending the ceremony, but Yoon Hee outlined her plot that caused their mother and child to have an accident.
Because the two children cheated on the exam, Dan Tae wanted his daughter to study abroad, and the boys stay, but the two brothers and Soo Ryun disagreed. Seok Kyu promises that if she let her stay, she will win the Cheong A trophy. Dan Tae's son - Seok Huyk asks him, is Seol A killed by him, Seok Huyk saw Seol A and Dan Tae in the technical department of Hera Palace. Yoon Hee is debt collection gangsters, Yoon Hee and Ro Na move to the house where Seol A used to live.
Eun Byeol knew that her parents used to quarrel, so she asked Yoon Chul to have dating with Seon Jin. Dan Tae knew that the couple they were going to date would get angry. After that Dan Tae made an appointment Seo Jin, Seo Jin lied to meet her father missed the date with her husband, Yoon Chul called his father-in-law to check.
Seo Jin went to meet Dae Tae and they got close. Yoon Chul and Soo Ryun both knew Seo Jin and Dan Tae had an affair but didn't know who the other party was. Soo Ryun told Dan Tae to take over her mother's furniture business, Soo Ryun still shows interest outside of her husband, but behind her there is another purpose.
Ro Na was late at school on the first day, but she was helped by Seok Huyk and the other classmates were disgusted with her. Eun Byeol invited his classmates to play at his house except Ro Na, the twins also refused. The twins invited Ro Na to the house, making Eun Byeol angry. Ro Na blamed Eun Byeol because her so Ro Na close solo, the two of them fought. It turned out that this conspiracy was devised by the twins, causing them to conflict.
Seo Jin discovered that Eun Byeol and Ro Na were fighting and got angry and scolded them. Yoon Chul discovered his wife cheating thanks to a follow-up message, and Dan Tae sent someone to follow his wife. Go to the scene where Dan Tae is tying Seol A to ask her to hand over the phone to hold her clip, the two quarrel, Dan Tae kicks her down.
Ro Na came to Dan Tae's house to play, invited by the twins. Soo Ryun invited Yoon Hee to Hera Palace, but when she returned, she was kicked out by Seo Jin. When the classmates knew that Ro Na was going to Seol A's home, her classmates teased her. Yoon Hee plans to sell Seol A's apartment, but thanks to the news that the government resettled the area, Yoon Hee is about to become rich. Everyone in the class bullied Ro Na, causing her to fall downstairs but fortunately one person took her hand. Who is that person we watch the next episode.