http://anidb.net/a8731

Synopsis
Nao moves in with Hazuki to begin their lives together. At first, she was innocent about sex, but Nao soon taught her to do it outdoors, 6-9, bondage, anal sex, using dildos and rotors, fellatio, etc. After a week, she had become a very lewd girl, but things are going to heat up even more from now on...

(Sequel from Houkago Nyan Nyan)