So since the recent surge in Vampire/Werewolf genre, it's possible to do a Star Trek twist.
Jim is a Werewolf by blood. It's been in his bloodline because his father was one as well. Could be that there is a planet somewhere with such a race and his father was "turned" and now Jim caries the bloodline just doesn't know it yet. So since the bloodline is fainter in Jim, it doesn't kick in until after he becomes Captain and they are off in their 5 year mission. So of course Jim's bloodline rears its ugly head. Jim is freaked out and Bones ends up looking into matters and figures it out for Jim.
Kind of like how the Thy'la bond has been used, now with the awakening of Jim's bloodline Jim has an "Imprint" bond. Wolves if anyone is not a aware, mate for life. So Jim doesn't have a choice in who he imprints on, just kind of happens after your awakening. So the first time Jim sees Spock after the awakening he imprints on Spock.
I want this fic to be angst in the beginning because Spock is in a relationship with Uhara. Jim is pinning away in misery, etc. However, Spock and Uhara are having relationship problems; Jim is just not aware of them. But, it does play out to Jim pursuing Spock after Spock and Uhara break up.
I want this to have a happy ending and feel free to play around with the idea. This is something that just popped into my head.
Bonus: If after the imprinting, everything month after Jim goes through his "transformation ordeal" he's pretty much in "heat" and needs to mate. So of course there's a couple days worth of sexathon to satisfy the mating urges.
Mega Bonus: If Vulcan's Knot during their mating and since Jim's awakening he knots as well during mating. So they of course must take turns in said "Sexathon" previously.
Have fun and Enjoy!!! Happy Writings ^^