What is this?

Abigail grabbed the bikini, about to dress but she froze. What the hell was this? She held the red bikini out in front of her: it was a tiny two piece string bikini! She never wore anything like this! It must be Stacy's idea of a joke!

Well, her sister hadn't thought out this little prank too well. Abigail could just put back on her previous outfit and walk out of the party! She went to reach for the clothes when the bathroom door swung open! Abigail froze, butt naked, clutching the red bikini as someone entered the bathroom. She was hidden by the shower curtain, but someone was in here with her!