Collaborative Drawings

I really like doing the black and white drawings but when I found out people were going to draw on it I got a little scared what they were going to do. It was a little nerve racking having someone else draw on my painting but I got used to it. When I returned to my drawing I was like oh my god what happened because I thought it was so good when I left it and when other people started to draw on it they kind of messed up my vision of the drawing. It wasnt such a big deal because I was able to fix it but I don't know if I liked that activity so much.