Cat takes Kara to the opera for some time alone in her private box.

Kara starts to lose control of herself under the influence of red kryptonite, leaving it up to Cat to take control instead.

AU: Kara is a Fallen Angel and Cat wants to make a deal with the Devil. Also, Kara will still be Supergirl, just not right away. Complete.

There have been several posts floating around tumblr about the tattoo that Kara has in the comics, and this tattoo!kink one shot is the result.

In which Cat is hunting Kara, but maybe Kara is hunting Cat as well…

Another way Cat could have found out that Kara was Supergirl... or the story I wrote to see if I could write fluff instead of angst. One shot.

Superman didn't find Kara right away, the government did. Kara spent the first year on earth being tortured and experimented on by people with access to kryptonite, and she still has the scars to prove it. Now, years later, can she find someone who will accept her the way she is, who will believe that she can still be strong and that she will not break? Complete.

Alternate way Kara could have realized she had lost her powers in "Red Faced," lots of angst. Involves Cat and Kara getting drunk. Warning for dubious consent. Complete.