They've passed the threshold where Sam sitting down would make Will twitchy or uncomfortable. They passed it back after magic potato. Will frowns a little, swinging his feet back and forth, toes just barely skimming the ground. The seat isn't even that high, but he's so small. He looks much younger than he is, but his tone is one of great seriousness: "What about a bear driving a monster truck? One of the ones that shoots fire." An important distinction.

Then he wrinkles his nose, crossing his ankles in sympathy at the idea of having a needle there. Arms and wrists are bad enough. "Why'd you get one on your foot? Nobody can really even see it." Clearly he assumes the reason to have a tattoo is so it can be seen.