Jonathan didn't look around to try and find who was following them. Doing otherwise would show whoever it was that they knew they were being followed. It could also communicate to the follower that they were panicked, which might give them confidence in what they were doing. "Where?" he asked as quietly as Captain had.
Jonathan raised his eyebrows. That was remarkable close. He wondered who or what was following them, considering that hardly anyone knew about the shards. And if it wasn't about the shards, it was probably bandits, or something like that. "What do you want us to do about it?" he asked.
Captain tilted his head slightly and then abrubtly stopped his horse, reaching over in a quick motion to stop Jonathan just in time to stop him from being crushed by a tree. The skullkim snarled and looked around as he heard laughing