...keeping herbivores and carnivores apart too much will result in consequences far worse than not doing so and trying to get along. They'd end up with a badly split society or even huge wars. Perhaps they'll even take half the world each and keep to themselves. The deaths and other bad shit that will happen would be FAR more than just a few deaths here and there.
Also, kozna, while I agree that used goods will always be far inferior to unused goods, this is not really that type of manga. It doesn't really matter since the entire story is like this and romance was never going to be about sex, there's too much drama and psychological shit going on, so it's not really bound down by the usual rules since I don't really care how many people a rabbit fucked(she's pretty much at the far end of the furry spectrum, any more and it'll just be bestiality, seriously, she's just a rabbit on two legs, nothing truly humanoid about her or the rest of the characters so the prostitute thing never bothered me since I don't get turned on by them anyway).
By the way, I also generally dislike used goods. It can depend on the story though, but generally it's nice if they're pure. It's kind of disgusting to imagine some other dude's dick ravaging the heroine before the mc gets her. Some cases aren't too bad though, like very old beings who had a lover hundreds or thousands of years ago, or someone who simply made a mistake or was raped once. That's acceptable. But unused goods will always be far more appealing. Maybe it's kind of ridiculous to think like that though