Sullvan is a blue, stick figure-like, dog. He has blue fur, and 3 hair tips on his circle shaped head. He has oval shaped eyes, unlike most of the other characters, and a long mouth. His ears are semi-circle shaped, and cover up a little half of his head. Sullvan has long, ovalish body. His legs, feet, and tail are in the shape of thin lines. He has thin arms, with mostly triangular hands.
In late Season 3 of Gumball Final Fantasy, his appearance changes multiple times. His fur becomes paler, and he gains bags under his eyes. He becomes a little skinnier, and his eyes are ever so lightly more red. It's unknown why he gains this appearance.
Sullvan usually has a neutral, average personally. He doesn't always bother getting involved in any problems, and is sometimes confused by most events.
- Sullvan has died twice so far.
- In The Rock (an old, abandoned, and unfinished story), he was brutally crushed to death by a large boulder. He was eventually revived in one an unofficial Gumball.MOV parody.
- In the Gumball Final Fantasy stories, it's possible that Sullvan died somewhere around The Final Fight saga, and was eventually replaced by an unknown character.
- Sullvan originated from an unnamed imaginary dog character Agentpman1 came up with.
- He has a brother named Hot Dog, who went missing in season 3 of the Gumball Final Fantasy stories.