The website for the upcoming original anime Just Because! has posted some new information about the series. We learn on the site that the series will be premiering in October. I say that this series is an original anime due to the story not being taken from a manga or light novel or any other original content. The link to the website can be found here.
It is winter of their third year of high school, near the end of second semester, when students have very little time in high school left. Everyone was just waiting for graduation.
Until he suddenly came home.
He was their classmate in middle school that had moved far away. His transferred in at a peculiar time, which reunited them. It was as if it were a go signal rang out to the feelings of the students who had just thought to end their high school life without fanfare.