Happy☆Lesson Advance
Japanese title: HAPPY☆LESSON ADVANCE
Alternative titles: Happy Lesson: Advance
Type: TV
Source: Manga
Episodes: 13
Status: Finished Airing
Aired: Jul 3, 2003 to Sep 28, 2003
Broadcast: Unknown
Duration: 24 min per ep
Rating: PG-13 - Teens 13 or older
Studios: Studio Hibari
Producers: KSS
Genres: Comedy, Romance
Themes: Harem

Hitotose Chitose is now living together with his 5 teachers as his mothers when a mysterious girl appears and becomes their neighbor which turns out that that person is Nagatsuki Kuron who wants Mu-chan to be her mother so another sibling rivalry ensues as to who would end up as Mu-chan's child. 

(Source: ANN)