Replying to She Wants The D?

K so this girl stole my friends phone and texted me on it and asked me if I wanted to f*ck her. she texts me everyday on his phone in third hour but this was just super random. I replied "what the heck?" She thought I meant like 'what the heck lets do it.' She replied"Eww no thats gross!" And then texted again "sorry he was looking over my shoulder." And then the bell rang for lunch so I didn't get to reply. I got a message from my friend saying it was him again. What should I do? Should I make my move next time I hang out with her? +k for advice.