You got it. 🙂 

Destiel

who’s the werewolf and who’s the hunter:
Cas is a hunter and Dean is a werewolf because I haven’t seen enough creature!Dean fics. 
who’s the mermaid and who’s the fisherman:
Cas is the mermaid because he’d have such a beautiful tail! And Dean would be so enchanted. 
who’s the witch and who’s the familiar:
Witch!Cas and Familiar!Dean is seriously my biggest weakness ever on the planet. Ever. 
who’s the barista and who’s the coffee addict:
Cas has gotta be the coffee addict. Sorry, those are the rules. Dean’s the barista who tries to flirt but Cas isn’t awake enough for it. 
who’s the professor and who’s the TA:
Professor!Cas (because sexy) and TA!Dean. 
who’s the knight and who’s the prince(ss):
Dean is a knight from an invading country and Cas is the prince They tussle or more than one occasion. Something about kidnapping for ransom and falling in love. 
who’s the teacher and who’s the single parent:
Dean’s a single dad, Cas is Emma’s teacher. 
who’s the writer and who’s the editor:
I’ll give Dean a break and make Cas the writer and Dean the editor. Cas loves to stress about his writing so Dean’s also there to stop the meltdown before it starts. 

DeanCasMeg

who’s the werewolf and who’s the hunter:
Cas and Meg are mated werewolves and Dean is a hunter who stumbles upon them while badly injured. But there’s something very strange about this hunter and it makes both Meg and Cas take pity on him and welcome them into their home. 
who’s the mermaid and who’s the fisherman:
Cas is a fisherman who nets a gorgeous mermaid named Dean. The only problem? His betrothed, the warrior queen Meg, hunts them both down. But she finds herself enamored with the strange man just as much as Dean is. The issue, of course, is finding a way for them to all stay close. 
who’s the witch and who’s the familiar:
Witches Cas and Meg share their familiar, Dean. 
who’s the barista and who’s the coffee addict:
Meg and Cas need coffee to live. Dean provides. 
who’s the professor and who’s the TA:
Dean and Cas are married professors who are very interested in Cas’s new TA.
who’s the knight and who’s the prince(ss):
Dean and Meg are both knights and they duel to find out who gets the honor of guarding Prince Castiel. Cas was planning on picking both of them but he likes to watch them bicker because it’s a little funny. 
who’s the teacher and who’s the single parent:
Cas is a single dad. His daughter isn’t doing too well in either English or Chemistry so that’s how he meets Dean and Meg. The issue is when he starts to fall a little for both of them. 
who’s the writer and who’s the editor:
Cas is a writer and Meg is his editor. It was all well and good when it was just them but then she had to take on a new client in addition and boy does this Dean guy get on his nerves. 

Send me ships!