Walter is tall and brawny. He has dark grey hair, combed back. He wears a pink vest with the UNWD insignia on the right breast, a grey utility sash, darker pink trousers, rollerblades and gliding wings. He also wears a visor.
He's got a very extreme personality, and acts like a total bro. He's exciteable, fast-moving and very reckless, rarely thinking before he acts. He's very restless, and strongly dislikes boring acts. He grows very impatient when his plans don't work, often performing the same act over and over until he succeeds.
He makes up for his poor intelligence and downright lousy concentration skills with his physical strength. He is very daring, and with a little determination, he can overcome any obstacle- by speed-skating, flying, wrestling or pole vaulting. He will not stop until he overcomes the obstacle in his path, even if it's painfully obvious that his method is... flawed.
Although he lacks concentration, he can hyper-focus on single tasks, and lacks an ability to naturally forget information. He also cannot feel pain from the neck down, and is trained to withstand extreme pressure, making him extremely hard to interrogate. He has total-recall memory and cannot naturally forget information.
When he was quite young, his father left his family. Although this affected Walter's brother Yannick more intensely, Walter did not entirely understand his father's disappearance, plagued ever-afterwards by a fear of rejection, as if the abandonment was his fault.
After this, he took up extreme sports, as well as working part-time as a courier for All-American Awesome. It was soon after they fired him that he had his accident - while abseiling, a nasty fall caused him to damage some nerves, resulting in him becoming incapable of feeling pain from the neck down. Coincidentally, he soon developed total-recall memory, and was hired as a messenger for the UNWD.
- He loves to eat, especially sweet food, and is entitled to a lifetime's supply of cheesecake, courtesy of Big Prize Enterprise.
- His speech patterns involve a lot of repetition, often tripling certain words or phrases, and he uses the word 'bro' a lot.
- He suffers from adult ADHD, and can lack focus or hyperfocus alternatingly, as well as a near-phobic fear of space and the void.
- Although he cannot feel pain below the neck, he can feel heat or pressure, as well as itching and tickling sensations, but if touch intensifies to the point where pain would normally be felt, it turns dull.
- Because of his total recall memory, he mostly delivers directions and messages, not material packages. Post Man is in charge of delivering those.
- His appearance is largely reminiscient of James Blond's - the visor and swept-back hair - this is due to Yang's idolisation of James, nearly to the point of it being a crush.