Odd almost always, be it subconsciously or intentionally, fiddling around with something with his fingers; more often than not he defaults to drumming his digits on a nearby surface (normally in some sort of rhythm), but he'll also flip a pen around, move a coin through his finger gaps, and occasionally (if the other person's fine with it) he likes to play with people's hair.

He also tends to bring an umbrella with him wherever he goes, regardless of how nice it is outside.