Could it be? She looks pretty good.

Checking the look.

Her mask needs a small adjustment?

She looks like she is getting ready to join her boyfriend in bed.

One last check before the light go down.

Or maybe that isn't her boyfriend in the other room.  Maybe she is really some other woman in disguise.  Maybe she is aiming to make love to her roommate's boyfriend.

She'd have access to the apt. She'd have access to her clothes and personal items.  She know her perfumes, her habits and her boyfriend.

After a long night partying, her roommate, might not mind getting her face cast, while she slept it off.  With a wig in matching color and style she'd look pretty good.

Secretly taping a few of their love making sessions, she might feel she could put it off.

Get him a little liquored or drugged up.  Turn the lights down and show him a little of the skin he is really looking for and she'd be in like flin.