"Er....you okay?" Oliver looked pretty worried. He had barely lost his balance, even though he had been clearly surprised by the sudden...well...collision. He offered a hand to the girl to help her up. He really should pay more attention to his surroundings but that Quidditch move had seemed so intriguing in his head that he'd not seen her.
"don't worry, really I'm fine." he assured her when the girl began to apologize. Of course it had to be a girl, he always felt awkward around those unless he knew them or talked about Quidditch with them. It was probably because most of the time they seemed rather amazed by him and he didn't know how to react.
He helped Ryann up and then let go of her hand again, burying both of his in his pockets out of habit. "I'm Oliver, by the way." he said, feeling like he should at least introduce himself, even if she probably knew him anyway.