Name: Odo 

Age: Unknown. Discovered year 2337, possibly as an "infant" at the time. I'm currently at Season 3, year 2371. Humanoid form resembles an adult, maybe 30-40 years of age. 

Gender: Gender is male. I'm not sure if the sex is also male.

Appearance: Odo likes to take the shape of a human, but he has problems constructing a realistic human face. He mimics the Chief of Security Starfleet Uniform--those aren't actual clothes. He also forms a working com-badge.[url=http://img4.wikia.nocookie.net/__cb20090823172446/memoryalpha/en/images/8/89/Odo_smiling.jpg]Odo smiling[/url] [url=http://img4.wikia.nocookie.net/__cb20120329225448/memoryalpha/en/images/0/00/Odo.jpg]Close-up of face.[/url]
Canon, AU, or OC?: Canon

Universe of Origin: Star Trek, specifically the Deep Space 9 series

Personality: [hider=Spoilers!]Odo has a deep sense of justice which he holds above all things, even so far to break laws, such as bugging Quark's--the local criminal--bar and quarters, so to make sure he won't do anything wrong. This may be an instinctual Changeling desire, as the rest of his species has done some unethical things to impose "order" on the galaxy. However, Odo finds their actions to be appalling. 
Odo has a hard time developing relationships with others. He built a sort of 'wall' around his personal life, which stems from a feeling of shame by being a Changeling and not a solid like everyone he knows. He feels very different. 
Having spent so much time with solids--the Changeling word for monoforms, aka species who cannot shapeshift--many of our interests and values have rubbed off on him. Occasionally Odo forms a cup in his hand and pretends to drink when with friends who are also drinking. He even attempted to eat at one point, but found it "high unsatisfying...and messy", as he does not have taste buds or a digestive system. 
Odo has friends on the station, mainly Major Kira Nerys, a Bajoran who knew him during the Cardassian occupation of the station. But, romance is lost to him. He does not have the instinctual need for romance and reproduction as solids do, and finds it to be too much compromise, and fails to understand our "obsession" with it. Once a Betazoid named Lwaxana Troi fell in love at the sight of him (after apprehending a pickpocketer who took her valuable, antique earring) and made many advances, both subtle and blunt. He found her to be very annoying. 
After finding his people, he developed a great interest in shapeshifting. He applied for his own quarters and filled it with all sorts of things to practice shifting into; artwork, sculptures, plants, and his old pail as memorabilia. A female Changeling told him that his species like to know what it means to [i]be[/i] something, and he wants to experience that. [/hider]
Abilities/Weapons: Being a Changeling, he can shapeshift into anything living and non-living. Rocks, plants, humanoids, etc; with enough practice and will, he can create a realistic copy. However, his attempt at a humanoid face shows that shapeshifting is really hard work. Rocks and simple lifeforms are easier. Odo is a rare Changeling, in that he never took part in "The Great Link", the joining of all Changelings in their natural liquid state. As such, assuming a form for more than 16 hours hurts, and he has to "rest" in "his pail" (a futuristic-looking bucket with a small hole in the top, so that he can get in, but no one can see him. He's ashamed of his natural state.) and regain his energy. Where he gets this energy is unknown; he doesn't need to eat, sleep, drink, or create waste. Odo carries a standard-issue Starfleet phaser, a gun which can be set to varying levels of force; most notably "stun" and "kill.". 

Backstory: [hider=Spoilers!]Odo is one of the 100 Changeling "infants" set out through the galaxy to learn. He doesn't remember anything before being discovered by the Bajorans, a race of humanoids. They sent him, in his natural gelatinous form, to the Bajoran Science Institute for further study. Dr. Mora Pol, the main scientist, had no idea he was sentient, and subjected Odo to painful tests, including exposure to a vacuum, numerous electric shocks, and a lovely trip through a protein decompiler. Finally Odo hit him with a tentacle, but still the Doctor didn't understand. Odo shifted into a perfect copy of a beaker and set himself next to a real one on a table. Then the unintentionally abusive tests stopped. From then on, they focused on his shapeshifting capabilities and dubbed him "Odo Itol", from [i]Odo'ital[/i], a Cardassian word that loosely translates to "unknown specimen." 
At one point, Odo formed his humanoid shape, taking the hairstyle from Dr. Mora Pol, and simply walked out of the Bajoran Science Institute. Later on he ended up on the Cardassian-run space station Terok Nor. There the Bajoran workers found him to be a good judge between arguments, as he was in a unique neutral position. The Cardassian rulers of the station also found this useful, and named him Chief of Security. Odo discovered his love for justice. When the Bajorans won the war against Cardassia and Starfleet took over the station, he stayed behind as Chief of Security. He's still there, fighting the unending war against crime. Spoilers![/hider]

Faction: USSA

Other: [url=http://img3.wikia.nocookie.net/__cb20060413094332/memoryalpha/en/images/thumb/3/3a/Odo_holding_his_bucket.jpg/300px-Odo_holding_his_bucket.jpg]Odo's bucket with a plant in it[/url]

((DANG I wrote a lot! Hope this is okay...))