...'s manga / #highschool student(22)

Chapters 1-2: siblings of a 3rd yr highschool, 2nd yr highschool and step sibling of 3rd yr jr.high but the 2 year gap step siblings are more closer.. Chapter 3: the teasing of student council president who was close with the 3rd yr eldest was unconsciously jealous towards the youngest for the attention from SC pres. Chapter 4: college student, convenience store part-timer former co-worker.

I learned in chapter 4 that there are people who can't calm down when not doing anything, they're much happier to do something or to help someone.