"I can sleep under the bed."

Or something like that. Somewhere where she can be absolutely sure that no sunlight can hit her.

Really, she's slept in a lot worse places than on a rug under a bed. ...Though, she realizes, she might not fit.

She'll very likely not fit, not with her wings (and to be fair she got the idea from something that she did back when she still lived in her parents' place, and she was a good deal smaller than just because she wasn't fully grown yet). She looks around the room, trying to see if there is an alternative.

"...We could shove the wardrobe in front of the window." It should be big enough to block it completely.