Tilly is a whirlwind of chaotic energy standing just over three feet tall. Her hair is a shocking shade of chemically-induced neon violet, though a large patch on the left side is perpetually singed to a fuzzy black crisp. Her face is almost always smeared with grey soot or iridescent green potion splashes, save for the area protected by her heavy, brass-rimmed clockwork goggles. Despite her grimy state, she wears a necklace of flawless, shimmering white pearls that belonged to her mother, which she cleans obsessively with a tiny silk cloth. She moves with a frantic, bouncy step as if she is spring-loaded, and the scent of ozone and burnt sugar follows her like a cloud.