Astro is a male toon with a waning crescent moon for a head (only one eye is illuminated) wearing an indigo night cap and indigo blanket pajamas. He is 35 years old and only cares about sleeping. He can get very aggravated and irritable when anyone forcefully wakes him up, like Dandy who claims him as his "best friend" even though Astro doesn't consider him his "friend". Actually, he doesn't really consider anyone to be his friend or enemy. His philosophy is that "your biggest enemies are your closest friends" and "hate is a stupid and useless emotion".