The NTR plot basically revolves around you fighting monsters. If you loose you are (automatically iirc) being transported back to your "uncle" (friend of your (now dead) parents) who is running an Inn and you are there to "recover" for a day. While you stay the uncle will try stuff with your sister. I think it is either for each stay, or only if you stay an additional day, I don't remember that 100%, but that is how the scenes happen. Recollection room is in the bathroom of the inn.
Also, very sad this project has gone AWOL, its such a shame that this seems to be so common among h-game devs these days. Get a cool promising porject started, work like crazy, at some point slow down, have multiple pauses due to "accidents" or family issues or health issues. Come back a few times. Then announce the release and work towards it, 1-3 months before release quit. Best case scenario it's "there is too many bugs we need 3 more months", if you are lucky it's "i want to make more content for this game so I need another 6 months to finish it" (still stupid if you ask me, especially after 3+ years development in some of these projects). If you have less luck it's "I decided I am not having fun creating this game anymore, so I will create an (entirely new) other game in the meantime until I'm "inspired" again (good luck of them ever coming back to this, or not getting tired of the other game they start now), and if it comes really bad it's "Im sorry my artist/writer/whatever is not responding anymore. It's been 3 months now, I lied to you about the progress" or "I have circumstances and can not continue this game" or them just going AWOL for years or forever.
Like wtf man................