@mischievousfires sent a meme:
Roxy had a tendency to tag after him when they were at the same lecture, whether he was the speaker at it or not. In this case, they'd ended up sitting together, or rather, she'd come in after him, saw he had a free seat beside him and helped herself.
As they walked, he was talking about the subject they'd just heard about (robotics, and the speaker was painfully behind Ratio's own research). Something he'd said made Roxy stop, and a few steps later, he noticed and turned back.
And then her lips were on his. He stood there for the couple seconds the kiss lasted. And then, "Did that satisfy whatever idle curiosity you had?"