少女玩具に忘却の褥を～健忘陵辱～

Assault on a younger sister suffering from the amnesia and her counselor!

Her immature undeveloped body gets thoroughly developed into the full woman.

A submissive sister heroine Hikari and her counselor, Aoi, who keeps an eye on Hikari

However, Aoi cannot go against the main character, for a very good reason.