Hitotose Chitose was always alone and untrusting of people but when 5 female teachers appear and started living together with him in his family's house as his mothers, things started to change and pick up, together with Hazuki-nee and Minazuki (his 2 sisters) everyday is a lesson. This series goes under two titles: Happy Lesson, and Happy Lesson Advance. Now, Happy Lesson has been dubbed and brought stateside, but Happy Lesson Advance can only be obtained stateside as fansub.