Don't want to be a perv (I totally am though) but I wish you showed more of her body; mainly for estetical reasons. I'm having a hard time figuring out how she is positioned. Sweet image though
Please don't upload prescaled versions. Especially if the picture is already so big 
The succubus' anatomy is confusing and inconsistent. I'm having a hard time spotting where her hips and legs are supposed to start. Are her horns supposed to be facing in opposite directions? Normally (with a real animal) you would expect them to be curling in the same direction. It seems odd to me that only one of her wings is transparent. Her left wing is much longer than the right one and has an extra horn.