This was a lot of fun to read, and I can see that you thought it out well. The whole bit where Onyx calls Pitch and Tooth her parents was hysterical. I laughed for at least three minutes and had to put my phone down at that point. This last chapter in particular was hilarious, what with the reactions to Tooth and Pitch being a couple. The concept of Father Time being seductive is also intruiging.
As for ideas for your Cavity collection, I have a few suggestions. I think it would be interesting if the other Guardians thought Pitch had Tooth under a spell, and she had to defend him. AU-ish things like a blind Tooth/Pitch or them as undercover agents/heroes/villains would also be interesting. Maybe one where Mother Nature and Tooth have a little talk over the latter's relationship with Pitch would be interesting. Song-fics are also good. Of course, I'm lousy at writing one-shots, and I end up making most of them into larger stories, but those are some of the ones I can think of that would be nice and short.

Wow this was such and amazing story. I am just blown away from this. I loved every moment of this. Excellent work all around. :D

hahahahahahahahaha, I can't believe there's actually a good well written Cavity Story out there!

Oh. My. Gosh. That was flipping amazing! I love love love love the Cavity ship, but there are almost NO stories for it. I'm really looking forward to that Cavity one-shot series/drabble.
Again, this was incredible! And I just adore the ending. I'm really glad Xion5 recommended it to me.

oh my god! I loved this SO MUCH! I loved the end it was just to funny and magnificient and arg, i dont have words to say it...i read this long time ago and FINALLY i can comment yei!

Do you even KNOW
HOW MUCH I LOVED THIS
LIKE OH MY GOD
POOR PITCH
POOR TOOTH
okay enough caps but awwwwww
Tooth has her faeries, Pitch has his fearies
ehhh? Ehhhhhh?
*PUNZ*

I'm not crying... I'm not... I just have some sand and feathers on my eyes, that's all... and the fact that this is beautiful has nothing to do with that...

Gah I read all of this in a day! It was so good! How you tease me though with the hint of makeup sex, the innuendos, and then the friggin heir thing?! Come on! There is no good smut with this ship and the more I read your stories the more I wanna see it! Lol but seriously, this was an awesome story. Great job

BY THE MOON THIS HAD GOT TO BE ONE OF THE BEST STORIES I HAVE EVER READ! I'm serious, it was perfectly balanced to fit the time and length, and the content was bang! Spot-on. I loved it and can't wait for more!

...whoa. I'm pretty sure when I read 'jumped onto him, straddling his waist with hands planted on his shoulders' "Show me your nightmares" WAS NOT what I imagined her saying.

OH...MY...GODDESS THAT WAS AWESOME! I have never been into short little fics like this but DAMN, yours pack an emotional punch!

HOLY CRAP HOLY CRAP HOLY CRAP TOOTH HOW THE HELL COULD YOU FORGET ABOUT SOMEBODY SO HOT- I MEAN SEXY- I MEAN DISTINGUISHING AS PITCH?! ESPECIALLY in a bird-worm that's as hot as that?! yea gods, I don't know if he deserves you birdbrain. Still, let's hope that you make it up to him.

...wow. just...wow. HOW did they go from that to- you know what nevermind. I'm just gonna keep reading.

OH MAN OH MAN OH MAN! I CANNOT WAIT TO SEE WHAT HAPPENS NEXT!

...good gods Toothy we all love you but you are SO DENSE! HOW could you not see that your dark bird- and I shiver when I use that name, but in a good way- is Pitch?! Gods. Oh well, she'll get there eventually.