Cavendish is a tall, thin man with short gray hair and a large handlebar mustache that is curled at the tips. He has a pale complexion and bright, turquoise eyes, often sporting a rather judgemental expression.
Dressing as though he's from the 1870s, Cavendish wears an olive green three-piece suit with coat-tails that go down to his knees. His brown vest features four gold colored buttons and the chain of his pocket-watch, and beneath this, he wears a white dress shirt with a pink tie.
He wears a small, matching green top hat with goggles, a pair of square, frameless glasses, and a pair of black and white dress shoes.
On the surface, Cavendish is generally a serious, self-focused man who can be rather rude to the people around him while being completely oblivious to his own shortcomings.
He has extreme dedication to his goal, regardless of what that goal is or how he decided on it. His focus on the task at hand often leads him to disregard logic, and this dedication to his sense of purpose remains even when Cavendish is acting against the direct orders of his boss.
Cavendish became a time traveler in hopes of saving the world and tends to see himself as 'the hero', often playing at leader while he's on missions with his partner. Despite this usual bravado, Cavendish occasionally falls back and becomes nervous and unsure when things get serious.
When he isn't focused on a task or a mission, Cavendish is much more willing to enjoy himself and has given in to Dakota's suggestions on a number of occasions. He is very much prone to goofing off alongside his partner, quickly agreeing to a bet in which the loser had to stuff his pants full of pistachios, and like Dakota, was very excited to go trick-or-treating for the first time.
Cavendish has shown himself to have a strong disliking for animals and a severe lack of knowledge surrounding them. This can be seen when he refers to a gummy bear as a 'rubbery-like-woodland-creature', and again when he asks Dakota what his costume was supposed to be, implying that he'd never seen a giraffe before.