What kind of sex might cause this?

[OneGreyElephantBalancing]

Out of interest, to help me satisfy my curiosity, what kind of sex acts might cause bruises on the top of mans thighs. Not on the inside leg but but at the front probably inline with end of cock ?

In my odd wonderings I came up with:
aggressive wanking,
aggressive doggy style sex (with a man maybe)
marks from stilettos somehow but not sure on that one

Maybe not sex related but seems likely in my highly sexed and very ex narc/ abusive husband.

What shape? In line with one another? I've had ones like that from whipping before... it only actually leaves fairly small bruises, not long ones very often.

Injury from playing on a fuBball table

If it's with say, a belt or a flat rope, you get shortish almost rectangular bruises.

Shagging someone who is perched or lying on a hard surface or table and your thighs bang against the edge.

well you asked ex was very thin she had boney arse when did doggy my pelvis hip bones use to bruise off her boney backside top of my legs ether side about inch round