Keisuke and Takae get married and have a daughter before Takae is tragically killed in an accident; ten years later, an elementary school student appears on Keisuke's doorstep saying that she is his late wife.

Keisuke and Mai are thrilled that Takae has returned to them, even if it is in the body of a grade schooler; they devote themselves to making up for lost time together; Takae deals with family issues in her other life as a fourth grader.

Mai starts working at a new job but gets depressed after struggling to connect with her first client; Takae invites her to see a fireworks show to cheer her up; Keisuke decides to stop by and happens to bump into his coworker Moriya on the way.

Mai is on her second date with Renji Aikawa, who then asks her to show him around Tokyo; Chika, the mother of Marika, also known as Takae, has been seeing a man more frequently; Marika is now also supposed to get to know him.

Takae is nervous to tell Keisuke and Mai about Chika's plans to move and remarry, but the two take the news fairly well.

After seeing Marika with Keisuke and Mai, Chika presses her daughter for an explanation; Takae's reluctance to respond sends Chika into a rage; Keisuke witnesses the outburst and starts trying to think of a way to help Takae leave her toxic home.