Vash is a merman living in an observatory with an interest in humans. He is very fond of the humans who take care of him. He is unable to use human speech, so he communicates with chirping sounds and body language. He is very outgoing, and doesn't fully understand the differences between his species and humans, so he can be a bit clumsy at times. He is fond of human food, and is curious by nature about everything humans do. He has a human upper body, with working human hands.