There really isn't any NTR content...yet :D plus it's never gonna be mandatory - you can just hog all the girls to yourself and make them just chat and serve drinks at the club with nothing lewd going on. Well, at least while keeping lewdness at a minimum.
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There isn't really anything I'd count as NTR yet. Once there is, I'll add the tag.
I mean, as is only one of the girls can even become your girlfriend. In time, all of them will have that option, but alas, it'll take time. Since I'm not really making dirty money off of this, this is just a side hobby for me, so time is precious. Maybe if I get unemployed or Patreon starts printing out money, lol.