The twins, Aoi and Akane, have been living with their grandparents from their late mother's side and their father. They are now fifth graders and are about to start taking steps towards life while embracing new encounters and new experiences on their own.
Life So Happy is a completed manga by Kouchi Kaede, first published in 2016. It blends romance, comedy, drama and slice of life. You can read all 19 available chapters of Life So Happy online for free on MangaPulse; the newest is Chapter 18, added 2021-12-02. The series is finished, so you can read it from start to end in one go.