If a human could survive up to 1,000 psi, I believe he wouldn't be flattened very much by her glutes. It might break a few bones though, because I think it would exert about 100 psi or so which some bones can't withstand. Sorry to bore you all.
It also depends on how fast the pressure is exerted. If you take 5,000 psi over the course of a day, you should be fine, but if you take it from a falling bowling ball, you won't have time to acclimate.
Let's assume she weighs 500 Newtons. If he's three inches tall, his surface area should be 10.5 square inches approximately. That's 47 pounds per square inch, enough to crush him when you factor in the decreased size of the bones.
