You would definitely get badly hurt if you have sex with a beanoid, not just because of their size and strength, but because of the radioactive fluids inside them, you can get burns just from touching their skin for too long. Inside their body is where all of the radiation is so if you're deep inside a beanoid or a beanoid is inside of you, you'll get burns, blisters, necrosis, things will open that shouldn't be open, and you may need to get amputations and you may also get cancer.