FIRST, some general setting background: Wolfwood comes from the distant future on a distant desert planet with two suns. Mankind arrived when a fleet of ships carrying millions in stasis crashed there 150 years ago. The planet is called Gunsmoke and isn't really meant to sustain life; without the Plants (living beings that double as an energy source and a producer of goods, contained in what look like enormous light bulbs) left over from the wreckage of the ships, the human race would have died out long ago. Think of it as an oldschool western with futuristic elements thrown in. Normally Plants are always female and can't leave their containers, however, there are two male autonomous plants who live on the planet as well and appear as normal humans: Vash and Knives.

BACK TO WOLFWOOD. Wolfwood spent his earlier years in a church that doubled as an orphanage until he was unknowingly recruited into the Eye of Michael, a religiously-themed organization of assassins that worships Knives. While there, he underwent training and physical modifications that greatly enhanced his body's strength, senses, and healing ability, however the increase in metabolism causes him to age faster. His age is never canonly stated, but I'd estimate he's between 16-18 years old (he appears late 20's/early 30's). He eventually betrayed and crippled his master, Chapel, and took his place and name in the Gung-Ho Guns, another organization of killers serving Knives more directly. He attempted to assassinate Knives while he was in a weakened state, but faced with Knives' sheer power, he was unable to pull the trigger out of fear for his own life. Knives then assigned him to watch over and guide his pacifist brother Vash.

After spending two years searching for Vash, following him around is what he spends most of his time in canon doing. Wolfwood is a rather multi-faceted character, but for the most part he's highly independent, survival-oriented, and generally follows a kill-or-be-killed philosophy. This is in sharp contrast to Vash, who refuses to take a single life and goes to suicidal lengths to save the lives of others. Vash's way of living is something of an anomoly to Wolfwood and influences him and his choices throughout their time together. In general Wolfwood is actually a pretty leisurely guy who tries to stay out of trouble, but it's not hard to piss him off or get him involved in troublesome things anyway (even if he loudly complains the whole time). He can be fiercely protective and has an iron will, often trying to handle things himself or interfere when he deems a situation is getting out of hand. However he can also be rather analytical with a strong sixth sense, able to judge a situation and decide what course of action gives the most realistic chance of success or survival.

You could say Wolfwood has an idealist's heart of gold, but he actively suppresses it in favor of being a realist. After all, growing up in a world where the strong devour the weak and the planet itself is barely habitable, it's not easy for a human to survive on naivete and optimism. But he is an idealist at heart, no matter how jaded and cynical he may be. His true agenda is to protect the orphanage where he grew up. That's one of his two most important motivations, the other being survival. (It's implied that disciples of the Eye of Michael undergo brainwashing to remove any worldly attachments to make them perfect devoted killers, but Wolfwood never let go of his attachment to the orphanage.) But even with those somewhat clear-cut goals he does occasionally bear the weight of the world on his shoulders, as he's deeply entrenched in a conflict between two superhuman entities that could (and nearly does) lead to the destruction of mankind.

But when it comes down to fighting for his life (or for the orphanage), Wolfwood can be something of a monster himself- or perhaps more like a wild beast. He will literally fight tooth and nail to survive, and he has an "extraordinary fighting instinct" that helps him gain the upper hand in any battle regardless of the opponent's strategy or skill. When he has to fight to the death he doesn't hold back- with some exceptions.

Last but not least, there's his derpy side. For all that Wolfwood can be very serious and gruff, he can also be rather comical and immature. It's a side we see the most when he's bickering with Vash and he's not above insults, light(ish...) physical abuse, and being cheap. He also claims to be a priest early on, and while he does seem to have some qualification in that regard, for the most part it's not taken that seriously seeing as he smokes, drinks, and kills people.