While I have not played the game yet, as I have a long backlog, I was surprised that it has a male main character. I always thought it was the girl with sword on her shoulder in the picture below your disclaimer on game page. Ok, now that I am looking for it, you tagged male protagonist. Why is he nowhere to be seen, except maybe certain parts of him. Is he ugly? Or is the vn in ego perspective and he does not have a face? It is partly on my backlog, because I fear, it is mostly a kinetic novel. You do have adventure genre, but from experience, the lack of gameplay in visual novel "games" is often not made very clear.
Your title suggestions are as bland as it gets. Princess Blade is even a movie title, and I thought the game is about a prince and not a princess. You might name a game about the advsery, like Diablo showed beyond any doubt. But Lilith is a horse ridden to death, imho. Unless you literally have her prominently in game including mythology and not just because it is a cool name and she is a demon. But she does not look very appealing, compare to the heroines.
There are several games named Tainted. You could go for a new name, yes, but all you have suggested is probably used somehwere as a name already, or a variation thereof (Most titles are). And none of them are sexy or indicate lewdness as well. So where is the benefit? I had a look at my lewd game collection. Most do not have a lewd name.
Tainted Kingdom
Corrupted Lands
Party of Heroines (and a Hero Prince)
The first I suggest for keeping the vileness and smut theme. Taint can be lewd. Princess is not. Neither is Lilith. You get her in non lewd games as big evil. The third I suggest, if comedy is more of an aspect of the game, as the females are so overly present in the screenshots, that one could forget that there is a (male) prince there as well. Maybe even include him in the capsule as an afterthought or partly out of frame for comical effect.
Also I would refrain from using a single girl for your capsule. She is not the hero, nor the goal of the game. If I see a capsule like that, I expect female protagonist single player and not what is probably a harem scenario. But if you insinst on such misdirection, the girl with the sword that looks a bit like a viking. But with more sword. But do not complain about players like me, that click on the capsule for the nice girl and go away after finding out she is only a side character among several girls to romance. Do not forget that people can refund games on steam within an hour or so.
I do not see the problem with your current "capsule" on itch. Oh, I see an intersting subtitle there. Escape the darkness save your kingdom. That gives inspiration to another suggestion.
Tainted Darkness - A Heros Tale. And Maidens. Lots of Maidens.