On the day of the high school entrance exam. Hiroto Inomaru who was traveling by train helped a girl who was about to be molested, she thanked him.
Coincidentally, they find out that they were attending the entrance exam for the same high school and they decide to go to the exam hall together.
In April, after successfully passing the high school exam, Hiroto meets her again as they were in the same class. She also seems to have passed without any problems.
Hiroto feels relieved and tries to share his joy but, in contrast to Hiroto, she seems to act strangely…