The kiss startles him, but it doesn't startle him enough not to immediately kiss back. He keeps it light and brief because he's still relatively new at this and he really doesn't want to mess it up. He's had one crush before, it took him ages to figure out it was a crush, and then even longer to do anything about it.

It's easier this time because he knows what he's feeling, and he knows what Alaric is feeling. But he still doesn't really know what he's doing, and it's hard to like someone else and not think of his boyfriend back home.

"I like you a lot."

It's redundant to say it when Alaric's a mind-reader. But there it is.