You're not alone. I do a lot of platonic character routes and just hang out using different player character archetypes to see how interactions differ. The whole casual hookups or taking every dick in town just don't interest me and are turnoffs so I avoid games that force you to play that way. I'll specifically look for games that allow virgin playthroughs since it indicates sex isn't obligatory.
If there is a love interest that catches my eye, it's more of a single-partner depravity playstyle. It's actually a bit of a peeve of mine that most games associate a protagonist with kinks as automatically being promiscuous or if you're in a sub relationship with one character you're just a doormat in all your interactions.
I primarily play this way too.
I usually keep 3 saves - the first save is when my Sveta is behaving well and has a sweet relationship with one of the guys, and that's it. I'll try to make her excel in most things like in school or in her modeling job. Since mother says she should not have her cherry popped yet (because of her own bad experience that my Sveta empathizes), she is saving until marriage - or at least until she's in college or moved out the house. You know, play it like how I'd roleplay in the world as a proper lady.
Then the 2nd save is when I want to switch things up to make Sveta a slut. Like, I'd go try every depraved sexual thing ever. Be a prostitute, a porn actress, a strip dancer, everything that's possible to do all the same time.
The 3rd save is like an alter version of the 1st Save file. But my Sveta is actually a magical girl. And she has a front - mom and everyone thinks she's a good pretty girl, that she has a sweet, innocent romantic relationship with a guy (with whom she doesn't have sex with, and he thinks she's a virgin). But then, she is secretly sexually active - hooking up anyone she finds attractive in the dance club and has a sugar daddy. In the older saves, she is also a succubus. I haven't yet tested if it's still possible for her to be one in the latest version tho but it's very likely that I'd make her one again.