She doesn't exist.
Younger girls are too finniky to do bbbj, not to mention their peer group disagrees with bbbj, even in the hooker sect. They think its gross or unnacceptable. Girls who are older that just look younger are smarter then an actaully younger gal and will make a smarter choice about such risky sex acts. Girls who are already doing bbbj and aren't young and dumb are probably doing so due to pressure of some sort. Maybe when they began it seemed like a great idea and now they don't wanna switch it up for fear of losing business. Maybe they had a partner who encouraged it at the time or even got off on it. Maybe someone told them that it was the only way to be, who knows but in my opinion any smart female who is above the age of maturation of mind is not going to be interested in putting strangers cocks in her mouth due to education. Likely if you find a girl who will do bbbj at a young age it isn't because she's made an educated decision to do so, how could she have? If she is older and doing so, she just doesn't hold safety at high value. Everyones different.