I had seen the original image on some website earlier today (it seems to be from some video game called "The Witcher 2: Assassins of Kings"), and instantly I thought of DxK, so I saved it to work on it after I get back from my vacation, but my brain decided otherwise, and so, here's the result:
original image:

result:

I don't like how Die's face turned out, because his picture was smaller than the base photo, so enlarging it caused pixelation and graininess, and no matter how much I worked with it, it only got worse instead of better. So the result that you see was the best I could get it to be. Even though it seems off place, as if it's a mask. It shouldn't look like that lol I also had to draw his hair manually, which was fun. I love drawing hair.
Working with Kaoru's face was easier. A bit of stretching here and there, and there it is. There's a way to stretch the face (or an image) that would make it seem that he's looking at the direction you want him to look, even if his eye is looking at the opposite direction. I couldn't remember how I used to do that, so I decided to skip it this time.
Okay, I'm talking more than the amount of images I have here xD