It's usually accompanied by something that appears platonic. For example, I e-mailed this guy I had originally met online after locating his e-mail at the university directory as I lost his # (he works at the university and had no other means of contacting him). And he mentioned something like "you could have just googled me as opposed to searching through the directory" and then he put a ;).
In our previous texts, he always used a ;) for practically everything, but it was usually after a seemingly platonic sentence.
Also, I may add, in person, he is not very outwardly affectionate.
Most Helpful Guy
Yep its flirting.0