I think it's a little too speculative, despite the posing and them being on the bed. They very well could just kiss and cuddle, which I think would fly in a G-rated movie, and thus should be within Safe. An immediate scene cut to imply sex would probably require PG, but the image doesn't tell us what comes next, hence it being speculative.
I'll definitely have to check with some mods on this.
As a note on PG-13, it can get away with more than you might expect on short sex scenes, like in one of the Twilight movies where there's a bit of humping and moaning and bed movement. PG-13 is roughly analogous to Questionable for our purposes.
Pretty sure it's Safe. The dance movement itself isn't that bad, and if she's pantsless, we're really just seeing a weird flat area, much like the anatomy of ponies in the show.
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