Monster Girls - Astaroth and Asmodeus

OP, the source you posted is from a a worthless art thief.

This is the actual artist: http://www.pixiv.net/member_illust.php?mode=medium&illust_id=6010615

Protip: If the gallery of an artist shows an inconsistent style, do a reverse image search. More often than not is an art thief. Specially in Deviantart.

I hear that. Unusual skin colors in general are my fetish.