@PotomacBobThere are at least a few instances of things ending in a 'blue balls' sort of way for my MC in Variation on a Theme. Of course, it's a very long story, so ... yeah. That's a tiny part of the story, but it happens, and more than once.
There are also at least two places where intercourse is avoided by a fraction of an inch (and stays avoided). I am pretty sure that orgasms are had (by both participants) in those cases, though - just not intercourse.
And there are more than a few dates where people get moderately worked up, but then go home.
Which ... is life, more or less. If you've got enough dating, some dates will be really good, but not wind up in a bed.
My MC is fairly definitively not a 'sex on the first date' sort of guy, which (of course) increases the number of dates which end short of anything 'happening' but where both people might have been amenable (even, sometimes, eager) for something to 'happen'.
Tagging it would be silly, so it's not tagged. If I tagged everything I could tag, it would be ridiculous. I feel like 'blue balls' would only make sense to tag if that was really a core part of the story, not a tiny element in a long, long story.