ok well here goes nothing this pic IS amazing. the concept is neat, and the heart in the background is the perfect shade of red. its not so bright that it hurts my eyes, but its also not so dark that ppl dont notice its there. Echo's eyes are as lovely as ever in your style <3 and i'm not gonna bitch about the shading cuz u use a soft shading style, which i personally like a lot. And it looks like there are multiple light-sources. If you were going for that, good job. If not, then I'd recommend sketching out a lightsource when shading that you can delete when done with it. Even though you didn't draw a line seperating Echo's forelegs, you made the indication with the white of her chest, which is amazing.
Now, Dusk looks more fox-like instead of wolf-like, but thats because the muzzle is so narrow. And his eye is off a bit. Its supposed to be closer to the forehead. But if his head is supposed to be tilted, then the other ear shouldn't be where it is. Now look at the part of the scarf underneath his muzzle. It looks more like its taped on him. I would've added some fur over the scarf to make it look a bit more realistic. And the scarf doesn't look like a real scarf, no offense. It looks more like tape. Colorful tape. Some more wrinkles in the scarf would make it look more like a real scarf, but not too many. Now Echo's nose looks tilted a bit too much. And her bangs look a bit weird next to her left ear (orange one). And the rose doesn't look much like a rose either (unless its just some flower and not a rose, then its fine, but im assuming its a rose..). I reccomend referencin a bit more when it comes to wolf anatomy and roses(UNLESS ITS NOT A ROSE! again, assuming)
I don't wanna offend you by this, I'm just saying what i think. I really do love this pic though