In the headmaster, one of the LIs is Debbie - she is a lesbian. As you progress her storyline, eventually there is a scene where you get her to give you a BJ, and she agrees, but makes you promise not to cum in her mouth. You have the option to warn her or not, if you do not warn her, she is nottttt happy about it lol (and she punches you in the balls immediately after so fair warning.)
In A House in the Rift, if you progress Lyriel's storyline, first there is a dream sequence (you enter her dreams a few times) where her sadistic guardian (aunt or something, I forget the exact relationship) puts her in a stock (I think that's what it's called, that medieval wooden thing with a flat board that has a hole for their head and two holes to lock their hands in place) and you have the option to facefuck her. Later on in her storyline she eventually begrudgingly starts giving you handjobs, then BJs, then sex, and initially she is not thrilled about it when you finish from the HJs and BJs and you have the option to paint her face or give her the old hot lunch. She complains either way, and this is sandbox so you have the option to do both multiple times, and in different settings (you can get 'service' from her after she washes the dishes in the kitchen most days, or if you catch her cleaning the bathroom there are a few ways you can get it to play out.)
Rance has loads (lol) of examples of this; in particular check out Sengoku Rance, Rance 6, Rance 9.
A struggle with sin has a lot of dubious con type content. You slowly corrupt the LIs over time for the most part. Thus, the early BJ scenes tend to be kind of dubious. There are various LIs that complain to varying degrees about getting a facial or protein shake. Also, the animation when you nut in their mouth is pretty epic, there is this whole bit where the MC's cock throbs and the LI's eyes tend to kind of open real wide in a look of shock as it's happening.
*Edit - I just saw your cum appreciation thread - dude if you haven't already you need to try a struggle with sin. The whole game is about cum lol. A witch casts a curse on you, making your dick grow huge and it makes your cum corrupt women automatically. So you go around sneaking cum into beverages to corrupt them, and when you get BJs or some facials, this corrupts them. People even try to buy your cum from you to use it to seduce women. And when you cum, it's a pretty massive amount.
Those are just a few off the top of my head, I am damn sure others on here can chime in with 5000 more, they just need to notice this thread lol.