First, one thing is a manga/manhwa with erotic (R) scenes and other a hentai.
Second, a hentai can be hetero, yaoi or yuri. Hentai being just hetero is a misconception!!
Trird, this looks as a low hentai with just s3x after s3x (Yes, there are hentais with plot).
Fourth, what really amazed me was Lezhin publishing this. I would really like if this develop a plot, but I don't think so.
Left at chapter 2
Dark Fall