A small t-shirt

You pick up a small white t-shirt that says "I Heart Dinosaurs" and bring it back to Batgirl.

"Here, this is the best I could do. It's better than nothing." You say as you hand it to her.

"I guess so." She says as she looks at the tiny t-shirt. She has to take her mask off to get her head through the little neck hole. She then squeezes her arms in and pulls it down over her tits. That's as far as it goes. As an added bonus, in the fluorescent lights of the security room you can still see her nipples through the thin material. "Better than nothing." The bottomless Batgirl repeats as she puts her mask back on.