oh god what is this.... PHYSICAL REACTION ≠ CONSENT OMG

What do you mean, " your mouth is saying no, but your ass is saying yes" isn't the same as saying yes?
LOL. But seriously, I think it's lazy storytelling, they don't want to spend time actually building a relationship so they go right to the sex. But it's worrisome because we don't want to normalize that behavior.

When I see this in stories I imagine a little cartoon butthole blushing and saying "yes"

Oh my goodness that's hilarious.