Most volcanic moon in solar system, cries on the inside. SHE FEMALE! SHE ALSO DOES NOT WANNA CRY ON THE OUTSIDE! Io is always angry, but she doesn’t really mean to get angry that much. Second densest moon, Galilean moon, Europa is her sister, Ganymede is her brother, Callisto is also her sister, Jupiter is her dad, Juno is her mom. Also Earth, Venus and Theia are her sister. Hates the moon Oberon for actually trying to make her cry on the outside.