Lost Time: February 1988 is the seventh chapter
The chapter starts with Satoru entering the classroom and the teacher arriving. The teacher asks him to take his seat and he accidentally sits at Hinazuki' seat. As he heads towards his seat, one of his classmates ask him if he liked Kayo, stating that they would make a great couple.
Later, Satoru runs home after lying to Kenya about his head hurting. He opens his house door using a spare key and is relieved to know that his mother is alive. He falls asleep while thinking about his mother's peaceful face and her last thought. He is woken up by his mother greeting him after she comes home. She then asks him what he wanted to eat. He realizes that it was a rerun and thought of it as a chance to save his mother.
After they're done eating, he thanks his mother and goes to bed. The next morning he is greeted by Osamu and he wonders if he has to redo all those 18 years to save his mother and thinks about why he was sent back. He finds the answer to his question after he sees Hinazuki. In class, Satoru and his friends talk about games and Kenya says that he likes their group because they have different interests and that he enjoys listening to them speak about it.
After that, Kenya asks if Satoru liked Hinazuki. Hearing this, Kazu decides to to help them get together despite his protests. When he confronts her, she asks him if he is dumb. He asks if they could be friends and she tells him that they're both impostors.