You crack me up. You're so steadfast to your wrong position. There's nothing bad about being wrong, but, in most cases, you'll just look like an ass if you can't admit defeat and keep arguing a failed position. I'm assuming you're a teenager because that's one of the first tough lessons teenagers learn when they start to the develop the "I know everything and all adults are idiots" mentality. Most people grow out of it but some never do and become eternal internet trolls that resemble the forever alone computer guy from South Park and live with their mother while only imagining what a vagina actually looks/feels like.
I'm sure the vast majority of men who have ever been fortunate to have regular sex with a female on top have enjoyed this motion lots of time with no injury. For one, I lost my virginity about 20 years ago and have enjoyed this type of movement almost monthly (more infrequently when single) since then. It's actually almost unbearably pleasurable because it's adding extra friction to the dorsal base of the penis head. My SO of over a decade really enjoys it because it uses your pelvic bone for more clitoral stimulation. What causes penile fracture is almost always a sideways bend, which this motion is not. The woman sitting up and "bouncing" is much more likely to cause a misalignment and fracture than this amazing motion.
Take a look at your penis, at the diagram on your penile fracture wiki link, and my link below. Because referring to sides of the penis as top and bottom can be confusing, we'll use ventral/dorsal like you would in an anatomy class. If your penis is aiming up towards your head, the side facing forward is the ventral side and the side against your stomach is the dorsal side. There are basically 3 long balloons in your penis (cavernosum). Two are on the dorsal side and on is on the ventral side.
http://en.m.wikipedia.org/wiki/Human_penis
In the gif's position, the penis is bending in two places. 1) at the base. Aiming your penis at your feet will cause harm but aiming it towards your head is exactly the way it is supposed to bend so I have to assume you aren't talking about that bend. 2) a ventral bend close to the head of the penis as she finishes her upward thrust. I assume this is the bend you have an issue with. However, with one cavernosum in that direction, you can safely mildly bend to the ventral side. Also, keep in mind that the vagina is not a steel cylinder without any give. It's made of a gloriously, delicious stretchy tissue. Hell, babies come through there. Anyways, with a rigid penis mildly bending in the dorsal direction in this position, you are basically rubbing the front of her vagina with your shaft but directing the head of your penis to the back and dragging it down the posterior wall of her vagina. Like I said earlier, she's likely grinding her clitoris against your pelvic bone for extra stimulation. She'd be having an amazing time and you'd be thinking about dead kittens and baseball in order to keep from blowing your load from the overstimulation after only 2-3 thrusts. Plus, boobs in your face. Never forget boobs in your face.
Bending towards the dorsal side, with two cavernosum, is much more risky, painful, causes a "clicking" sound, and could also lead to a fracture. It's the two dorsal cavernosum that don't like to bend so sideways bend is also risky. But, don't be scared to enjoy some mild pressure bending ventrally or you'll be missing out on one of the most mind-numbing feelings.
Always use protection, but if you're still so hardheaded and refuse to see that your opinion isn't accurate, please triple bag your cock as we don't need any more inflexible ignorant asses in the world.