She starts duty soon

Supergirl looks at the clock on the wall. 5 minutes until her shift. She looks down at her top, that now doesn't fit. She also knows that her drawer is full of tight T-Shirts. She'll have to borrow clothes from Power Girl, across the hall. She uses her X-Ray vision to check the hallway is clear before running out the door. She quickly gets to a door and knocks it loudly before covering her huge breasts with her hands.

Power Girl answers her door, fully costumed, having just finished her duty. "What the hell happened to you!?" She asks, upon seeing the big titted, half naked Supergirl in the corridor.

"My breasts just grew and none of my tops fit! Let me in!" She shouts. Power Girl steps aside and Supergirl runs in. You and Zatanna sneak in after her.

"What do you mean your your 'breasts just grew'?" Power Girl asks confused.

"I don't know! I was looking at them in the mirror and they started growing!" She responds.

"You didn't do anything to them?"

"No!" Supergirl insist, embarrassed about her wish. "You have to let me borrow a top, I start duty soon!" She says, changing the subject.

"Okay, but I just came here to get changed, before and after duty, all I have is the top I came in, or this." She gestures to the costume she's currently wearing.