Up til now, Tadpole Jackson has mostly been awkwardly hovering close to elbow, helping move Ignatius as he's directed, though he's looking increasingly gloomy about the whole thing. The tadpole doesn't have enormous emotional depth, but what little he does have is consumed with gentle humming anxiety. He doesn't understand the full implications of what's going on, but he does know one thing... Eruka isn't here.

Which means when Ignatius suddenly jerk like that, his immediate reaction is to startle and slap at the movement with his tail, less to pin him down and more out of reflex.