Etymology: alternate pronunciation of uchiwa 団扇 "Fan"
Like their canon counterparts, a majority of the Uchiha are black-haired and eyed in their human forms, something that remains consistent in their Demon and Berserker forms. Being ravens, their Demon forms maintain the scruffy all-black plumage, complete with throat feathers.
Like most shinobi, the Uchiha are fluent in Japanese and English. But when they use the Sharingan, they can instantly learn, understand, and speak other languages from reading a foreigner's lips or handwriting, even something as foreign as Arabic or obscure as Latin. Also, they communicate with each other with sounds they mimic from their surroundingsclicks, beeps, rattling, chiming, etc.
Unlike most clans, there is no rhyme or reason to the names of Uchiha members. They're not named after body parts (like the Inuzuka), anything pertaining to the sun (like the Hyūga firstborn), gemstones (like the Anokudatsu), nor do their names have a set prefix (like the Aburame, Yamanaka, Nara, or Akimichi firstborn). This is because the Uchiha aren't born with a name; they choose it themselves.
When an Uchiha is born, they are given the name Kogarasu ("Child Raven") until they're old enough to fly, speak, and feed themselves. On the birthday after they've proven themselves old enough, they're sent out to find their name. For reasons cited above, the aforementioned naming themes are forbidden, as is naming oneself after a deity or anything pertaining to their species. Often, these names are nouns, concrete or abstracti.e. Itachi naming himself after the first animal he saw, or Mikoto naming herself after a title associated with deitiesand always in Japanese.
For the most part, the Uchiha are even-tempered, with a sense of humor that can range from dry to just plain cutting or dark, with a side of mischief. They're also very intelligent which, like the animal they're based on, allows them to find ways to survive any climate no matter how harsh, and to think of solutions to problems in high-stress situations.
Also like ravens, Uchiha tend to cache their food/possessions
and steal the same from other Uchiha. This is actually considered necessary, if not annoying, as they consider it good practice for when they become shinobii.e. retrieving enemy documents without knowing how heavily guarded or booby-trapped it is.
Another thing Uchiha love to do, like their species of demon, is to go flying, especially if they can perform feats such as flying in loops. In fact, much like caching and stealing, such feats are encouraged, as it prepares them for dodging attacks while in flight. In fact, Jewel Foxes are often asked to assist by shooting the spherical forms of their Gem Barrage at random intervals and within the Uchiha's flight path.
Like the corvids they're based on, Uchiha will eat anything that's edible. Nuts, fruits, vegetables, eggs, bugs, meat, carrion. And in the distant past, human corpses. It was in fact this last staple of their diet that caused their forebears' evolution from ordinary corvids to Humanized corvid demons after consuming the dead flesh of none other than the God of Shinobi himself. But further into their history, some would succumb to a terrible degenerative disease of the mind and body, causing the survivors to give up their generational practice. Eventually, they encountered the Anokudatsu, a skulk of kitsune who could turn dead matter into precious stones. Thus, the Uchiha of today wean themselves from necrophagy by gathering dead matterdead animals, dead Mt. Oinari civilians, dead enemies or missing-nininto corpse scrolls and giving them to the Anokudatsu to work their magic.
Rites of Passage
After choosing their own name, the next Uchiha rite of passage is the ability to use their most basic technique, the Grand Fireball. As soon as that is mastered, the Uchiha in question will be allowed to wear the clan's namesake symbol on their clothes. Also, they will immediately go to the main temple of the Anavatapta Shrine and go to the secret meeting place under the seventh tatami mat from the right. Once there, the Uchiha in question will read and memorize everything etched in the tablet about the clan's history.
Like their canon counterparts, the Uchiha of Mt. Oinari also have the Sharingan that allows them to copy non-Bloodline jutsu and can advance into Mangekyō. But unlike its canon counterpart, this version of the Sharingan comes at a price for its natural bearers: eisoptrophobia, the fear of their own reflections. This phobia is not without justification either, for if Uchiha are to look upon their uninterrupted reflection the following will occur based on their Sharingan level:
Dormant: 72 hours of unconsciousness
Awakened: 72 hours of migraines
Mangekyō: 72 hours of migraines and seizures
There is, however, an exception to this: if the Sharingan user is not a born Uchiha, they're immune to this phobia.
Also, this Sharingan cannot be taken by force; it has to be given by the natural bearer. Otherwise, once the stolen Sharingan is implanted, it will implode the thief's brain or gangrene the body part in which it is implanted.
The Mangekyō Sharingan also has its costs. Once activated and depending on jutsu usage, the user will be blind in that particular eye for 72 hours.
The Mangekyō Sharingan can only be achieved by going into and reverting from the Karasu Tengu berserker state for the first time. This state is induced by consuming pills made from the panther cap mushroom and as the name implies, takes the form of a tengu with corvine characteristics. And much like the ancient depiction of tengu, this berserker state renders the Uchiha in question little more than a bloodthirsty killing machine, their intelligence supplanted by bloodlust and unable to distinguish enemy from ally. For this reason, they only induce this state as a last resort and warn their allies to clear their line of vision. The Uchiha in question will revert back to their normal state once their bloodlust has been sated or if they see their reflection. Once reverted, the Uchiha will be rendered feeble and unable to use chakra for 72 hours.