Running to find her
Hermione wasn't as naive as she let on; she knew damn well what she, or at least her presence was doing to Ron, and she couldn't lie - she liked it.
She liked knowing that he was 'turned on' by her, that he was turning red and flushed other places than his face and neck. She briefly thought of whispering that he was doing the same to her as well, but was afraid he would do something irrational, like tear his clothes of and run screaming into the Restricted Section.
The thought made her laugh inwardly.
She kissed him back, tangling hands in his hair, pulling him as close as possible and letting her heat flow over him.