No way am I downloading 400 images one page at a time from g.e-hentai, so I found some archive downloads.
Vol 1:
http://www.filesonic.com/file/1578635274/
Vol 2:
http://www.filesonic.com/file/1578623964/
Very strange manga in general (done by the same guy as Okitsune-sama de Chu, so yea) Seems to involve a ghost(?) girl (she's a bit of a dick) who's collecting eggs from possessed(?) girls. She needs the key penis (yes, really) that grows from the main girl (Minori Sakurahoujou) to unlock the possessed girls so the ghost can enter and take out the egg. And of course the possessed girls have strange powers (cue a different fetish each chapter) and there's lots of sex in-between.
Ch 1 features weird man arms that grow out of people and the ground.
Ch 2 features the BE and it's quite nice. Minori and another girl slowly fill up a small room.
Ch 3 is about panties and tentacles.
Ch 4 is about dogs and turning into dog girls.
Ch 5 is about fairies (as they're called in the manga, but they're more like gnomes). First they capture Minori and tie her up. Then they shrink her. Cue normal-sized possessed girl + shrunken Minori.
Ch 6 is swimsuits and water.
Ch 7 is eating food off a naked girl. Plus a new antagonist (Sakuya) is introduced.
Ch 8 isn't anything in particular.
In Ch 9 Sakuya and Minori finally meet.
Ch 10 is tights/stockings and bodysuits.
Ch 11 features a nerdy painter girl who's into bondage.
Ch 12 features a monk girl and snakes.
Ch 13 is another story chapter with Minori and Sakuya.