Mosi is a compact grippli with long spring-loaded legs and a broad, soft-jointed posture that makes him seem ready to leap even when standing still. His skin has the matte texture of river stones beneath a film of rain, mottled olive along the back and yellow-green across the throat. His jaw is wide, and his small blunt teeth show whenever he speaks, eats, or laughs. He smiles often, but the expression is difficult to read because it looks halfway between kindness and the warning display of a cornered frog. His movements are quiet until they are suddenly not, carrying him from crouch to ceiling beam in a single elastic motion. Despite his marsh-born appearance, he keeps himself immaculate, smelling faintly of soap, crushed basil, and old copper. He checks the little brass clasp at his collar every few breaths without realizing it.