it might mean shes just curious to know what you look like. If shes a girl you've only met online i highly recommend you not showing it to her. it might not even BE a her maybe a sexual predator.
First of all why do you want picture of a girl with you, without any occasion or party, sometimes when unknown guys come to a girl in a party and ask for a picture with her, she feels irritated. I am also a girl and I have pictures with so many guys in parties or functions on their request or groups, but in the cases they were in my class, college or friends of friends. You cannot approach an unknown girl for a picture with her.
Means that the girl became part of the story
Everyone is different, with different agendas, so the only way you will know for sure is to ask her.
He pulled out his yearbook and drew a picture of her.
You keep it
do you mean to get her attracted to you well that depends on the girl
Either is a possibility, but assumptions lead to bad results. Just ask the guy.
it can mean anything most likely that she likes you but it doesn't have to mean that. if you don't know why or how she has the picture then if i were you i would worry =D
marry me
He likes you
They are interested in dating you.
When a girl mentions picture day means that she cannot wait to have her picture taken. She will probably remind everyone about picture day.