To be fair though, if you choose not to be interested in Lyssa's extras, you won't find out, so it's just a BJ by a girl, and you have dealt with worse. After all, the Fetish Locator app (in game) will entice you to do a lot of stuff and you cannot be guaranteed that everybody will be to your liking.
That is also what I want to add to your otherwise correct observations: the premise of this game - playing the FL app - in essence means, despite all choices, that we will see more weird action, maybe some we are uncomfortable with, than in the standard "Young man comes home to his landlady after 8 years" fare. So I have accepted stuff in this game for the reasons you lay out that I probably would count as a minus in most others - it fits the story.
This does not extend to Lydia though - I mean, I have accepted her as a forced LI even though I considered the smittenness (is that a word?) completely overdone, but the story premise did not necessarily call for any LI (as opposed to fuckbuddy) at all.