A hentai manga from last year. It is a hentai adaptation of one of the
Japanese Urban Legends called "
Hanako-san of the Toilet"(
https://en.wikipedia.org/wiki/Japane..._the_Toilet.29)
While the manga doesn't have an English translation yet, it seems that
Hanako,
the loli ghost, keeps growing each time she absorbs a man's semen for some
reason.
She rapidly grows from loli to teen and teen to adult during each of her
different sex events with the protagonist. However, as if she has absorbed too
much semen, she reverts back into her loli form in the end. You can read the
whole manga here:
https://hitomi.la/reader/795055.html#285 (Click left arrow for the next page)
The reason I brought up such an old manga is because it's getting an
anime adaptation on the upcoming 22nd!^^ Screenshots+PV:
http://www.getchu.com/soft.phtml?id=874327