could have saved himself, and the h, a lot of heartache if he'd noticed one little thing about that virgin prostitute - the carpet didn't match the drapes. Alas, he didn't so spent years looking for what was right under his nose. Oh, this was never mentioned in the book itself but really, he spent all this time looking for a dark haired woman when he knew she wore makeup and used a different name. It never crossed his mind that she wasn't actually dark haired. And...how could you not know? Couldn't use the excuse that her drawers covered all since he ripped them off.
Sorry. I just find it laughable that he went years and 300+pages under the illusion the woman he was looking for was actually a brunette.
Regarding their relationship, I got the feeling he avoided her. She lived next door. And he avoided her. Much of the book took place over the course of...a week maybe? That's a danged long time to avoid your neighbor, particularly when you find yourself becoming irritably attracted to her so quickly - that week or so. You'd think as cranky as he is, he would have confronted her during those several years that were written off-page.
As for her, some of the things she did were downright irrational. Really? You live in London, neighbors on both sides, and you strip down to your undies while outside painting? It never occurs to you that others can see you? The wall may go over your head, but does it block the upstairs window?
Other things - the villain. It took 'til now for the inspector to notice the connections of these dead women. And...they started after the nutburger realized the h was actually a strawberry blond. Why then, why not before? I find it difficult to believe that he hadn't killed before.
The h's sister - considering their background, she seemed terribly sheltered.
The h's mother - why was she letting her daughter handle all her late husband's problems? Why was she oblivious to what was going on? She wouldn't have been THAT old; why did there seem to be this impression that she wasn't in much better shape than the elderly gent who married the h.
Beyond that, there's the usual keeping of secrets from the soul mate, the harsh reactions when they come out (even though if the soul mate had been a little more observant, there wouldn't have been any secrets.) Lying isn't ok, but neither is being willfully blind. The resulting attack on h while H is off nursing his pride...yeah; these are a bit formulaic when you think about them.
OTOH, it is nice that you have a H who is actually capable of being the villain's worst nightmare when provoked. Too many - historical and otherwise - have heroes whose fitness is as improbable as their fighting skills (or their ability to discern danger). It's a bit harder to feel anything other than an eyeroll when a foppish H is trying to defend his h from the sort who'd have him for breakfast - and somehow he comes out on top. And while at some point, I'd hope the author creates a H who hasn't had the need to learn how to maim and kill. Of course, I'd hope she doesn't put said pampered prince in a position where he needs to fake it to save his h.