It makes sense from a why standpoint. I can’t help but wonder about the how.
How did we evolve reproductive organs that are not only sensitive, but also release reproductive cells at climax?
I’m ok with a “we have no idea” answer, but if there is an answer I also want to know.
Nitpick: evolution is often random mutation that doesn’t produce a negative impact. For example, a random mutation in humans producing certain hair colors is not negative, but doesn’t necessarily give an advantage either, so we have a distribution of hair colors.
(I’m ignoring people having a thing for people with a certain hair color because I doubt it’s statistically significant. If anything, it’s probably more an unconscious preference for people with uncommon attributes, meaning more genetic diversity.)