That sorta depends on the rest of the image. Here's a list of what and what isn't considered. Personally I'd say this is more suggestive-ish since while the focus is on her gluteus maximus we've seen similar shots on the show itself and there doesn't seem to be anything overtly sexual about this.Incidentally: if you ever have questions there's a forum for such things and an IRC chat where there's normally always a mod available to help sort things out. Or, in extremis, you can report the image as "other" and ask a mod to come have a look.