It happens! You've drained the lube, you're relaxed and ready to go, and then you brace yourself for impact on the wall in a not-so-secure way and with the first thrust, snap goes the digit. You could wear a brace, or, a less nerdy option, brace yourself on your big penis-having partner.
Penile fractures are a legit real (and terrifying) sounding thing! Sure, there's no real bone to break in a boner, but there are blood vessels that can and do get snapped. For guys with big dicks, this commonly happens when they are thrusting to hard in a woman with a short canal.
His dick can't bruise your ovary. Bodies do not work that way. BUT if you have an ovarian cyst, his big dick and all that vigorous sexing could rupture a cyst making you feel like an angry little Donal Trump is stabbing your ovary with a pitchfork. This has absolutely happened to me, and that is why I am voting for Hillary.
His big dick absolutely CAN bruise your cervix. This has also happened to me. It still does from time to time and my bedfellow gets far, far too proud of himself when I announced that he broke my vagina. Your cervix is the little trap door that keeps your baby making house safe attacking penises. If you aren't properly aroused, your cervix will sit lower, making it easier to bump and bruise. Even if you ARE as wet as hell, a long penis can still come a knocking on your door like an unwanted vacuum salesmen who you are also having sex with.
An overzealous big penis having guy will be eager to get himself inside of you. All of himself. If he tries this sans lube, he can scratch your vaginal walls. Nice and slow and easy does it when you start out having sex with a larger than average penis.
Please to see above. Yeah. Those scratches can turn into big old tears, both externally and internally, if he just barges into your vagina like he's Dick Van Dyke and this is his very special TV home. Tell that eager beaver to settle down if he ever plans on making it to syndication.