She also exchanged your underwear

"And there is something more." Alison pulled another thing out of the bag. A small piece of lacy red fabric hung from her finger. It were a woman's panties. You mouth dropped open seeing the sexy lingerie.

It took you a few seconds until you realized something. Quickly you stood up and unzipped your hot-pants. Alison looked with wide open eyes at your strange behavior. As you pulled the hot-pants down, she and you saw what you had feared. Not only were their panties in your bag, but you also were wearing a pair. It was a red thong with shiny triangular part covering your penis and testicles and lace trim. It matched the red bra you wore before. Shocked by your discovery you sat down on your bed.

"Well Alex, seems your 'girlfriend' has a thing for boys wearing girl-underwear." Alison could barely refrain from laughing.

"I'm so going to tell her." You swear angry at the redhead. It took you a nearly a minute until your anger had faded away. "And what do we do?" You asked your sister.