Episode 4 recap: Yan Mo, as Gu Yan Zhi's nanny, opens Gu Yan Zhi's heart.

Song Ranran believed Lu Fei Yan's words and returned to the art school where she first met Gu Yan Zhi at the agreed-upon time, waiting for another encounter with him. After arriving at the school, Song Ranran reminisced about the scene of seeing Gu Yan Zhi playing the piano back then, and at that moment, Gu Yan Zhi also arrived at the art school.

Song Ranran and Gu Yan Zhi met, and Yan Mo immediately played a romantic piano piece, but it unexpectedly triggered unpleasant memories for Gu Yan Zhi. For some reason, Yan Mo didn't develop any feelings for Gu Yan Zhi, while Lu Fei Yan believed that the beginning of the rupture between Song Ranran and Gu Yan Zhi was the photo taken by Song Ranran, so they had to find the photo to discover the reason.

Yan Mo couldn't find the photo in the office and thought it must be at home, but she couldn't enter Gu Yan Zhi's house, which was a headache for her. Zhou Han Zhang went to find Gu Si Yu and told her about Gu Yan Zhi and Yan Mo. Surprisingly, Gu Si Yu already knew about it and acknowledged Yan Mo as her sister-in-law.

After Zhou Han Zhang explained the situation to Gu Si Yu, he informed her about Yan Mo and Little O living together and insisted on investigating it at Yan Mo's home. Little O happened to be recharging on the rooftop, and when Gu Si Yu arrived, she called him down and questioned him about the time he spent with Yan Mo. Little O explained that they had been together for more than five years, leading Gu Si Yu to mistakenly believe that Gu Yan Zhi was the third party. However, she still supported Gu Yan Zhi and wanted to force Little O to leave.

Little O stated that he would protect Yan Mo's safety and would not leave her. Zhou Han Zhang then threatened Little O without courtesy. Sensing Zhou Han Zhang's ill intentions, Little O activated his defense mechanism and attacked Zhou Han Zhang and his bodyguards.

After dealing with everyone, Little O walked directly in front of Gu Si Yu. She thought she was about to be attacked, but to her surprise, Little O didn't harm her. Instead, he handed her a cup of coffee and sweet-talked her, making Gu Si Yu very happy.

Yan Mo appeared, and Gu Si Yu immediately interrogated her. Yan Mo lied, saying that Little O was their adopted younger brother, and they only had a sibling relationship. Gu Si Yu understood the situation and found Little O cute, so she quickly let go of any grudges.

Yan Mo was worried about not being able to go to Gu Yan Zhi's house. Seeing that Gu Si Yu liked her, she lied and said she wanted to pursue Gu Yan Zhi but couldn't get close to him, so she asked Gu Si Yu for help. Gu Si Yu learned about the situation and immediately took Yan Mo to Gu Yan Zhi's house as a nanny, allowing Yan Mo to stay there.

Gu Yan Zhi didn't want a nanny, but he couldn't tolerate Gu Si Yu living in his house, so he reluctantly agreed to have a nanny. To his surprise, the nanny brought by Gu Si Yu turned out to be Yan Mo, and she even forced him to serve her, which made him angry.

After Gu Si Yu insisted on Gu Yan Zhi treating Yan Mo well and left his house, Gu Yan Zhi reluctantly took on the role of the master and instructed Yan Mo on what to do.

Gu Yan Zhi went to work at the research institute, while Yan Mo stayed home alone, waiting for Gu Yan Zhi to return and also searching for that photo. However, no matter how hard she looked, she couldn't find it.

In the evening, Gu Yan Zhi came back home, expecting Yan Mo to be a submissive servant who would cook for him and serve him tenderly. But to his surprise, he arrived home to a different scene. Yan Mo hadn't cooked anything and was hungry, waiting for Gu Yan Zhi to come back and make food for her.

Gu Yan Zhi didn't expect that the nanny he hired would act more like the master than the owner. He was particularly angry, while Yan Mo acted spoiled, claiming that she didn't know how to cook and was very hungry. Gu Yan Zhi's heart softened, and he allowed Yan Mo to go to the fridge and get dumplings, preparing them for her to eat. However, Yan Mo didn't even know how to do that properly, and the two almost bumped into each other in front of the fridge.

Gu Yan Zhi and Yan Mo had close physical contact, and their hearts raced. Yan Mo was relaxed and even taught Gu Yan Zhi how to do a "wall slam" (a romantic gesture in which one person pins the other against a wall). This frightened Gu Yan Zhi. Finally, Yan Mo found a photo of Gu Yan Zhi's mother, which she didn't know the significance of, and Gu Yan Zhi happened to see it.

Gu Yan Zhi took the photo away and told Yan Mo that she didn't need to clean the study anymore. Yan Mo didn't understand what was going on and could only call Gu Si Yu to ask for clarification. After the call, Yan Mo learned that it was Gu Yan Zhi's mother's memorial day, and Gu Yan Zhi was definitely feeling unhappy because he missed his mother.

Gu Yan Zhi went to practice fencing alone, hoping to release his pent-up unhappiness by sweating it out. However, the unpleasant feelings still lingered. When he returned from venting, he suddenly realized that the photo was missing. He didn't know what happened and searched all over the house. After searching for a long time without finding the photo, he could only suspect that he had left it at the fencing hall and someone had mistaken it for trash and thrown it away. It was the last photo of his mother.

Yan Mo didn't want Gu Yan Zhi to be sad, so she went to the garbage at the fencing hall and painstakingly sifted through it, searching for the photo. After a long search, Yan Mo finally found the photo. She carefully kept it and planned to surprise Gu Yan Zhi by giving it to him when he returned home. However, Gu Yan Zhi wasn't at home.

Gu Yan Zhi didn't have his phone with him, so Yan Mo couldn't reach him. She could only ask Gu Si Yu for information and try to figure out where Gu Yan Zhi might be at that moment. Gu Yan Zhi went to the place where his mother taught him to play the piano, reminiscing about his mother. As soon as Yan Mo found out, she rushed to give the photo to Gu Yan Zhi, hoping to comfort him.

Yan Mo showed concern for Gu Yan Zhi, and he couldn't help but express his love and longing for his mother. He had been trying to suppress his emotions and was thus leading an unhappy life. Yan Mo reminded Gu Yan Zhi that it was okay to miss his mother, as it meant that he still remembered her. She then took him to see the stars.

Yan Mo explained that deceased loved ones become stars and continue to watch over them in a different way. She encouraged Gu Yan Zhi to place his love for his mother in the stars.