Okay, so we'll try to stay within the framework of what's already going on.

That in mind...

Lex Luthor paid the Joker to kidnap the Mayor, and hand the body over to a new criminal gang in Gotham named the Mutants. (Yes, from The Dark Knight Returns.) What Luthor had to give the Joker to get him to play along might terrify you. Lex does this to cause a special election for Gotham's Mayor, and to cause headlines that Batman is turning Gotham into a war zone---not a safe city. The Mutants' play along to gain instant infamy, and because their secret master wanted bait. The secret master, the vampire known simply as the Monk when he's around (and the Mad Monk when he's not), KNEW Batman wouldn't be around with Freeze's actions. He wanted Batgirl and Robin. Damian lives because the Mad Monk willed it; he wanted an explosion big enough to incapacitate...not kill.

He underestimated Batsuits. 

Luthor attempts to make Gotham's elite and political powers his proxy after realizing he fights a two fronted war with Superman and Batman teaming up so frequently to foil him. Luthor plans to have his candidate, Hamilton Hill, win the special election. Luthor seems to have allies within Gotham elite, but so far they're staying mysterious.

The Mad Monk, in true classic vampire horror fashion, begins snatching girls from Steph's campus. Batgirl's going to notice, and eventually get herself kidnapped. Meanwhile the Mutants begin to rebel against the control exerted from the vampiric Monk, or maybe just from the awful things he's done to them.

Two story threads that begin together but stray off in separate directions so people can go between the two, or stick with one if they get an idea for it, etc. This was the story plan after the 'Night Out' mini-episode. 

So, tell me: how's your character fit into the above? That is, how do you WANT them to fit into the above? Surely we can spin some plates and make everyone happy.