User blog comment:Xano501.ben/A reason why Ahri can hear Sona/@comment-5331854-20130725160046/@comment-5331854-20130726093416

Well, did I say that she shouldn't hear Sona? I just gave you another reason for her telepathy XD

For some reasons, Summoners and champs don't have much of a relationship that goes beyond "I choose you, Champion!", so Sona getting attracted to Ahri because of her "mindhearing" ability (doesn't matter if stolen Summoner powers, gumiho-heritage or both) is a natural thing. Humans are social beings.