Kim Min Gyu has wealth and success, but lives an isolated life due to his allergy of people. He then meets and falls in love with a girl who is pretending to be a robot for her ex-boyfriend, a genius robots professor.
After the farewell, Ji A becomes heartbroken. When Min Kyu calls her about another delivery service, she says it can't be done and that she's going far away. Meanwhile, Ji A coincidentally spots Min Kyu and Ri El together.
Ji A and Min Kyu meet on the night of the meteor shower. They confront each other and talk about their feelings. Meanwhile, Ri El gets told that she will be marrying Yoo Cheol.
Min Kyu asks Baek Gyoon is his falling in love with Aji 3 is included in her deep-learning, to which Baek Gyoon denies. Min Kyu confesses about how he has always waited for Aji 3 to come in the morning. However, Baek Gyoon tells him that that's because he has spent too many years on his own.
Min Kyu finds out that it may be possible to cure his allergy. He begins to have high hopes. Meanwhile, Baek Gyoon gets nervous about Ji A becoming closer to Min Kyu and decides to leave him.
Min Kyu decides to leave, but he finds himself keep finding excuses to stay at least a moment longer. Even after leaving, Min Kyu ends up coming back to Ji A. Meanwhile, it turns out that Aji 3 has made her own backup folder to keep her promise.
Ji A plans to go to Australia, but Min Kyu interrupts her. Ji A lies, saying that she was just a model for Aji 3 and that they don't know each other. Meanwhile, Yoo Cheol's team steals a file from Santa Maria.
Wanting to kiss Ri El, Min Kyu gets a lesson from a special instructor. When the day comes, Min Kyu and Ri El go on a date. Worried something might happen, Baek Gyoon decides to tag along.
Ji A comes every day to Min Kyu's house to give him food. She tells him that she'll keep coming. Meanwhile, Min Kyu finds out that Ji A is the creator of the Heart Balls.
Baek Gyoon decides it’s time to change the face of Aji 3. He decides to leave the patterns of the emotions she procured and delete every video including the private ones she took of Min Kyu and Ji A.
Min Kyu makes Aji 3 do petty chores around the house. Baek Gyoon sees this and offers to do the chores himself. Meanwhile, the real Aji 3 is almost done with the adjustments.
Ji A becomes sad that she has to lie to Min Kyu. Min Kyu and Ji A spend time together for one last time before resetting the memory. After the reset, Min Kyu feels her absence.
Despite Min Kyu's efforts to win over the Santa Maria team, the day comes for Ji A to leave. In order to keep Ji A by his side, Min Kyu shows Baek Gyoon his allergic reaction.
Baek Gyoon becomes worried about Min Kyu's condition and wonder if it's okay to keep having Ji A as the replacement for Aji 3. He soon realizes that it is because he still has feelings left for Ji A.Watch Now:Amazon
Yoo Cheol learns about how Min Kyu got his allergy. He makes his mind up regarding the emergency board meeting. Jin Bae tells Min Kyu that he wants to resign.Watch Now:Amazon
The childhood story behind Min Kyu's condition gets revealed. When Min Kyu gets a reaction, Ji A gives him an injection and earns his trust. Meanwhile, Min Kyu doesn't have a clue how to deal with Ye Ri El.
Baek Gyoon tells Ji A that she just needs to wait three more days until Aji 3 gets fixed. Min Kyu takes Ji A out to the restaurant where he meets Ri El and her father. Meanwhile, Min Kyu goes to see Sun Hye and asks for her opinion.Watch Now:Amazon
Min Kyu finds out everything, and due to shock, his allergy to humans creeps up again. He is hurriedly taken to Seoul. The Santa Maria Team and Ji A can't do anything but watch him.
Baek Gyoon finally finds Doo Sam, and Martin flies into Korea. Martin is running out of patience, and Do Won promises to deliver Aji 3. Min Kyu comes up with a plan to protect Aji 3.
Ji A invites Min Kyu over to her house in order for her brother to get his job back. Ji A pursues her own business while Min Kyu and Yoo Cheol work together to lead KM Financial.Watch Now:Amazon
Ji A steals Min Kyu's first kiss, and Min Kyu is flustered by his feelings toward her. Meanwhile, Ji A is hurt by the fact that Min Kyu is trying to keep his distance from her.
Min Kyu and Ji A get stuck inside a storage room. When Min Kyu tells his hon-est story to Ji A, she gets more heartbroken, but decides to send Min Kyu away.Watch Now:Amazon
Do Won tries to get Jin Bae on his side. While having dinner with Ji A, Baek Gyoon finally understands why she broke up with him. On the day of the final screening for start-up items, Yoo Cheol suddenly decides to participate in the event.Watch Now:Amazon
Ji A gets delivered to Min Kyu's house. However, they are off to a rough start as Ji A makes a mistake right from the beginning. Ji A must improvise and convince Min Kyu that she is an AI robot.Watch Now:Amazon
Min Kyu tells Baek Gyoon that he likes Aji 3, and Baek Gyoon is shocked. Meanwhile, through Doctor Oh, Ji A finds out that Min Kyu does have a human allergy. She's scared by the fact that she could have killed Min Kyu.
Min Kyu meets Ji A on the train. He decides to follow Ji A to her destination. Ji A is in danger of getting her cover blown.