Haha go for it, thats what there good for. Myself know a few and im 20 years old but the reality is that I look like a 15-17yr old. They werent that prevalent when I went to highschool, girls are growing up very quickly.
i wouldnt, she probably has these diseases in her mouth....
i think that if she offers, then its most likely that she has a disease of some sort, or she was just messing with you to see if you would actually do it.
and probably yell out "RAPE!!!" when you pull out your tool...