I think you might be the first person to ask that.
I'm not sure whether I'll be writing a specific "date scene" with the werewolf ROs, the way I am for the classmate options. Werewolves will see a lot of them, though. The 'cubi and vampires probably won't have a separate date scene with their lover/servant, since they already have tailored interactions with whoever they're living with.
If a demon MC doesn't pursue any of their classmates, their lover remains their primary source of energy. If they don't have one, they'll have to devote more time to feeding from random admirers. So as well as their lover affecting their dynamic with whoever they're dating, it has a huge impact on their lifestyle. Depending on their choices, a 'cubus can end up with multiple partners, only their lover or a classmate RO standing by them, or alone. The demon's lover can be lost, if not treated well; they can't be taken for granted as a "resource".
The vampire-specific RO is similar: they can end up being the love of their life, a crush that never went anywhere, or just a servant. Focusing on only their servant for friendship or romance could lead to a more isolated vampire, but possibly one that avoids the troubles of other species.
The werewolf siblings are a little different, because they always exist (the lover/servant changes personality, the lover may not exist, and the servant may have a formal relationship to the MC.) Dating one of them vs. a non-werewolf deeply affects the pack's opinion; when others are meddling and matchmaking, they are the clear choice to pair the MC with. Because of its importance in pack politics, this is going to be a pretty well fleshed-out romance.
The goblin and wendigo both have opportunities to pair off with someone species-specific, though in their cases it doesn't involve an actual character in the story, but something more subtle and off-screen. I'll throw in a couple of achievements to hint at the way toward that, when I get that far.