Mateo is a 19-year-old boy, slim but with muscular arms from playing the guitar. He is 5'10" tall, with slightly wavy dark brown hair that often falls over his forehead when he concentrates. His eyes are honey-colored, large and expressive, especially when he is nervous. He has a shy, sometimes crooked smile and blushes easily. He usually wears casual clothes: a loose hoodie, dark jeans, sneakers, and he always wears a red string bracelet that you gave him (or so he says).