In Bava Kamma 27a we find the following scenario:
If a man fell from a roof and was inserted into a woman [due to the force of the fall, but with no intention to engage in sexual intercourse,] he is liable to pay the four types of indemnity [damages, pain, medical costs, loss of livelihood]. And if this woman was his yevama [waiting for him to perform levirate marriage], he has not acquired her [as his wife through this act of intercourse. ]
I have trouble understanding how, in the mind of the Sages, this scenario could possibly unfold. Were the two people naked, as they would have to have been? Wouldn't that be of probability zero? Wouldn't the woman had to have been lying down, not erect? Would the man not have had to have been aroused, also with probability zero under the circumstances?
This is not a frivolous question. I know the Talmud is full of unlikely scenarios described to illustrate the law. But this one is beyond unlikely. Why is it there?
If the teaching is that unintentional intercourse does not count, there are plausible scenarios for that. I believe there must be more to this story.