itch.io

First off, your game is fantastic, the NTS route currently a lot better then the NTR one but both really good.
Love the "select" chapter" part, and would if you could add a bit more clarity into what exactly the "+nts" and "+ntr" means. For example, right now I have no idea if there is unique content hidden behind selecting about 50%/50% of them, only NTS, only NTR, neither of them... and so on.

That out of the way... your storyline is PERFECT for some early on bad endings. I would be very surprised if the MCs heart is not soon planning to get better, the heart monitor find its way back to female main character and we can "listen in" to her increased heartrate, which is awesome and all...

But if that is the sort of content you can get behind, please add some "gone too far" content on both NTS and NTR route.

One example is in the current NTS path, it sounds like "being blacked" is an option right around the corner. In addition to the other options you already intended, add a "cursed" branch we can select (with warnings), preferably from Vi's perspective, where she just loses her head completely and Nate is no longer her priority.

And it continues for just a few iterations down before it get endings like:
"Vi and Claire both gets conquered by this man and focus on him and each other, they get Nate fired and blocks him and live happily without him as he sinks into depression, only getting a taunting and censored video or two once in a while from the bull rubbing it into hes face what he lost"
"Vi dumps Nate over text and blocks him. Nate seeks solace in Claires arms and finally have sex with her. She rejects him the next day, telling him that she understood perfectly why Vi left because he did NOT live up to the expectations... and he is stuck working there as their lovers keep passing him on the career ladder"
Maybe one where Vi wants to dump Nate for him, and Nate can choose between letting it happen or begging for "some kind of solution" and end up pussyfree in permanent chastity while Claire tries to tell him he deserves better and should go with her instead but he much rather end up as a slave to Vi and her new boyfriend (and perhaps eventually husband) with no chance for intimacy ever again then not having Vi in hes life at all
and if you are ok with extreme content:
"Nate confronts Vi about feeling ignored and down prioritized. Vi pretends to be sad and edges him, promising to include him more and show just how much she loves him, and promises him he can watch her with her lover live the next time, cuffed to a chair by the side of the bed. When the scene happens, she just ride her lover and tell him that she had switched out Nate's heart medication with one that increase heart rate instead, and the mc just get more and more blurry and inaudible watching and listening to them having sex until it is implied he gets a heart attack while they completely ignore him"

Anything like that.

And by all means, ensure all the "cursed path" endings actually end, you don't want to have to maintain that path all the way to the other ends, but of course would be awesome with other cursed paths later in the story as well if there are other people then me who love those. I know those kind of endings are really popular in games like The Shadow over Blackmore and such, but they aren't intended to be slow burn.