An alien, then? Alright, so... Are you a Jeija?
JeijÃ¯ are native to a very lush garden world; the closest approximation to their name for it is Otrini. It is approximately 10000 km in diameter, so its gravity is approximately three-quarters that of Terre; this has produced an ecosystem full of slender, gangly plants and animals. JeijÃ¯ are actually unusual in that respect: while they have the slender limbs typical to their planet, they are much smaller than most animal life; an adult female (typically a handful of centimeters taller than their male counterparts) stands about 60 centimeters tall on average. This means that, compared to their larger alien counterparts, they are somewhat weak and fragile, but extremely fast and dextrous. They are even unusually nimble for their size, making excellent pilots, mechanics, and sharpshooters.
Terran scientists note that they have several traits that resemble those of terran cephalopods, including well-developed eyes and brains, tentacles, and bioluminescence. A Jeija in conversation will largely-unconsciously change the color, pattern, and brightness of the luminescent cells on their mantle; these flashes and colors add connotation, emotion, and intensity to their words. Non-JeijÃ¯, even prominent xenolinguists, have extreme difficulty interpreting these cues, so JeijÃ¯ have a reputation for sounding very deadpan and unemotional.
As a small species on a planet of large species, JeijÃ¯ have evolved a number of adaptations to aid their survival: while omnivorous, JeijÃ¯ have a very slow metabolism normally only seen in sedentary herbivores; this allows them to consume very little, meaning they have to hunt and forage only rarely. For those times when they are in a vulnerable position that may expose them to predation, they have an acidic spit they can launch over impressive distances with notorious accuracy; in addition to being painful and caustic, a well-aimed spurt can cause permanent blindness.
Culturally, the JeijÃ¯ have a reputation for being thoughtful, polite, and careful. They live extremely long lives and reproduce only rarely; a 400-year old will probably only have two offspring, and wouldn't expect grandchildren until 700 or so. In the unlikely event that a JeijÃ¯ survives the centuries to die of natural causes, they can expect to see 1200 or so; the oldest Jeija to date is currently alive and recently celebrated his 1623rd birthday.
Current estimates place JeijÃ¯ populations at about 250; JeijÃ¯ society emphasizes the rights of the individual and peaceful cooperation rather than enforced rules. There is no JeijÃ¯ government, and no code of law on Otrini. JeijÃ¯ scientists are notoriously clever and inventive, and Otrini's tech level is even higher than that of some established Governance species.
Or are you perhaps an Afu?
Afus come from a planet they call Zharu; it is extremely inhospitable to humans, and indeed most sapient life: the atmosphere is choked with carbon dioxide and large organic molecules, and the seas (which cover some 30% of the planet) are primarily bromine. Only slightly smaller than Terre, Zharu's atmosphere keeps the temperature at a level most species can survive, but are extremely uncomfortable in; conversely, an Afu on another planet will likely feel unpleasantly cold without some sort of climate control, and will require a breather mask to provide the cocktail of gasses they need to breathe.
An individual Afu is actually not an individual; any given Afu is a collection of tiny lifeforms, connected by a hive mind and led by a queen: the vaguely-hominid bodies seen by most are actually something of a living hive, a biological construct operated by the tiny beings inside it. The red area on the front contains the queen, who in addition to producing drones to sustain the colony has a number of sensory organs that her subjects lack or have stunted versions of; she communicates this information and directs the colony's movements and activities. Even the queen herself, however, is largely unintelligent: any Afu component on its own acts solely on instinct and is largely helpless; only when they are together and communicate do emergent intelligences become apparent.
Due to their unusual neural structure, which is actually composed of thousands of Afu drones specialized for data storage and communication, Afu have a natural knack for psionics, and actually discovered them independently well before space travel. Even an untrained Afu will probably have a power or two. Their many-in-one nature also gives them unparalleled reflexes and speed of thought, but requires much more food and air than a normal being of their size (an average hive stands between five and six feet tall).
Afu are fiercely democratic, allowing any adult colony to weigh in on any matter of government or law that it chooses to; non-Afu are often surprised by that fact, given that an individual organism has next to no free will or identity. Afu languages typically use a word meaning closer to "we" than "I" to refer to oneself, but most that learn alien languages or deal with other cultures adapt their speech patterns. Afu have little in the way of "typical" personalities: where one can make somewhat accurate guesses about the general personality types expected from many species, Afu personalities are as varied as humans'.
Given their alien outlook and psionic powers, some sapients maintain prejudice against Afu even in the relatively cosmopolitan galactic society. Since their technology is less advanced than most species and they are distinctly less detached from their biological roots than many, they are regarded as dangerous savages by the prejudiced minority.
If you are a Jeija, what gender are you? And either way, what's your name?