You might not want it to be the case, but
"It took her a moment to speak. Her voice came out furry and delicious. “I’m giving him the energy I took earlier. It’s . . . slowing down the damage his Hunger is inflicting. But it’s very bad. And I’m almost . . .” She licked her lips. The sight of it made me want to rip off my shirt and start boasting of my many manly deeds. “. . . empty.” She made the word sound like a sin. “I’ll need to feed if I’m to give him more.” "
Peace Talks page 319.
At least she's says herself that she is almost empty and I don't think she is lying.
Sure sure, I'm not doubting that she said it, or even that she's being honest.
But she shouldn't be, right? I mean, we have reason to believe that she's being around for a couple centuries. She's the head of the Wamps, and after years leading them, and feeding whenever and however she wants, she should be closer to Lord Raith's power levels than Thomas's.
But she's tapped after an hour of feeding Thomas after numerous meals within the day? She's been using her hunger to beat down Lord Raith's demon, to the point that he's apparently a puppy. And she's presumably been feeding him enough to keep him alive for the sake of the charade.
So to me she's either lying and is actually as powerful as she should be, or she's not and she's inexplicably weak.