need some diffuse texture on the alien, just looks like flat color. wall's a bit too clean.
and some better composition and context, storytelling stuff. right now it kind of feels like an arbitrary crop of a render from a sort of arbitary perspective.
if this is supposed to be the varginha alien thing, (which I only heard of now from anon above), then perhaps it would be good to set it more from the perspective of a passerby who may spot the alien. something that makes the viewer feel more like the passerby who might notice this uncanny figure near a wall.
i, myself, am only studying these kinds of things, like composition and making good pictures, so i'm no expert, but try to think of it as an actual situation happening. what i see is just an alien and a wall, and i didn't know exactly what was going on before i learned a little about the varginha thing. make more of the scene surrounding the alien, make context for the alien to stand out in. with more of a scene, you could point the camera away from the alien, leave them closer to one side, looking at the scene more generally and letting the viewer take in the image in a more "neutral" way, without you directly emphasizing the alien by pointing the view at them. that's one variation of something you could try or think about.