Why is she drooling? Why does he have happy face? And most of the pics by this artist are some type of taboo. I think that would be more than enough of a reason for this to be sex. The stealth sex in this is so evident that it makes yu question it.
I think just the fact that there's a debate about whether it's sex or just sexually suggestive confirms the latter. Just because it would only be tagged sexually suggestive doesn't mean it CAN'T be sex . . . it just means you have to use your imagination. Which you have to do, with this image.