I was 16 and my girlfriend was 15 at the time. We were walking home from and Wendy said she was desperate for a poo. I told her to do it in her knickers, but I never imagined that she would actually do it. She said she'd always wanted to do that in front of a boy but she was afraid I'd think she was weird. I had a hard on and she looked down at the bulge in my trousers and said it looked like she was wrong. We kissed and she put her tongue in my mouth while she felt my erection. I put my hand up her skirt and felt her bum and Wendy warned me I might get a handful of of poo if I carried on. I said I didn't care and Wendy told me to finger her. I put my finger in her pussy and fingered her until she came and she started filling her knickers. I was so excited I came in my pants and Wendy told me she wanted me to make love to her but I didn't want to do that until she turned 16.