A QUICK AND EASY GUIDE TO THE ENTIRETY OF THE INUYASHA UNIVERSE
INUYASHA: Title character, disputed if main character. Pretty, jealous, indecisive, eats small children. Picked last for kickball as a kid, very angry over that. :( Except for high school fanfictions, his personality remains mostly unchanged from the original.
TETSUSAIGA: Also spelled Tessaiga. Inuyasha's sword, has the power to rape the ground and kill over 9000 demons in one swing. Big, upright, and stiff, later becomes red and pulsing. Possibly the most important character in the series, probably shows up the least often in fanfictions.
KAGOME: Bipolar. Either totally loved or completely dispised in the fan community, there seems to be no middle ground there. Reincarnation of Kikyo, looks exactly like her. Except she actually doesn't. D In fanfictions, is usually made a selfish, emo bitch, or will be totally cool and smart. Despite never having been established as a priestess (omgspoileruntilthelastchapter) in the actual series, will commonly be referred to as "miko" in fanfiction.
SHIPPO: Largely ignored in both fanfiction and the series itself, will disappear from storylines for a little while in both. Unnecessary character. :)
MIROKU: Pervert. Often overlooked is his obvious intelligence, balance, and skills, like his ability to keep up with Inuyasha as they run. But clearly as he demonstrates "perversion" an average of once every 20 chapters, there is nothing else to him. In fanfictions, his perversion will be magnified, covering the existence of all else.
SANGO: Demon slayer. Often reduced to nothing more than shouting "HENTAI!" slapping Miroku in fanfictions, but her personality seems to remain mostly the same. Also known to shout "ECCHI!" and slap Miroku. Because it makes sense to shout the Japanese pronunciation of the English letter "H" in feudal Japan.
FEUDAL ERA: When the series - except for Kagome's time stories - takes place. Probably actually 1496 or 1497, covers a period of about 1400 to 1600. Often referred to, incorrectly, as "fuedal", and sometimes the spelling deviates more and more. One such example is "fuederal".
SESSHOMARU: Inuyasha's very pretty older brother. Covets the tetsusaiga up to a certain point. Has moon on forehead - fights evil by moonlight? Although never having shown any romantic affection for any character in the series at all, is constantly paired up with Kagome, Kagura, young or aged up Rin, sometimes Kikyo, and quite often an OC. Other fairly common mates are Naraku, ocassionally Miroku, and very often, his own brother. Because incest - and pedophilia (Rin, and I guess Inuyasha, sort of) - is DAMN sexy.
JAKEN: Sesshomaru's servant/toad/youkai/thing. Personality is possibly the least changed in fanfiction.
RIN: Sesshomaru's ward. Relationship with Sesshomaru is argued a lot - some say it's a father/daughter reltionship, others insist they're attracted to each other. Once again, because pedophilia is sexy. Who says a 900 year old guy and a 7 or 8 year old girl don't belong together? Fanfiction's young Rin's personality usually stays the same or close to the original's.
NARAKU: Only real villain of the series. Seems to be the least hated character in the series, though (whereas Miroku, Kagome, and Kikyo seem to be among the most hated. The only arguments for Miroku and Kikyo are like "pervert" and "clay-pot". Like that's really their faults. Kikyo was brought back to life against her will, and Miroku's a teenage boy. The nerve!). Many fanfiction writers can't think of anything good to do with him, so the parody and humor writers steal him and make him do diabolical yet utterly ridiculous things, adding to the humor of the story. Often made a lover of Sesshomaru.
KAGURA: Seems to be ignored a lot, but is usually rather level-headed if somewhat pissed... in fanfiction and in the series. Loves Sesshomaru, but is not usually allowed to pair up with him. Dies later whoops spoiler.
KANNA: ...
SISTER SUE: Unnecessary original character, a sister of Inuyasha and Sesshomaru. Seems to mostly be younger than Inuyasha, occasionally older than Sesshomaru or in the middle. Sometimes also related to another character, most often also an official character in the series. Sometimes a love interest of another character, sometimes powerful enough to destroy Naraku very easily.
MARY SUE: Any original character created by the author/artist with a common, undeveloped personality. Commonly a demon, will be paired up with any character of the series, will often have a past/background that is very similar to whoever she is paired up with. Usually very powerful, enough to easily destroy Naraku, or any other demon. In parody/humor fics, is often killed off or revealed to be something else by the end.
GARY STU: A male Mary Sue, not very common.
KIKYO: Fondly referred to as a "clay pot" by much of the fan community, almost always treated as a cold-hearted bitch whose only goal in life is to drag Inuyasha to hell with her. In the actual series, she stops trying to do that after volume 8, and switches to trying to destroy Naraku. Her motives and methods are deep and secret, and by the time of her final, actual, second death, she fully redeems herself. In high school fics, often starts out as the popular and slutty girlfriend of prep!Inuyasha, but she gets punched out by goth!Kagome, then loses Inuyasha to Kagome.
OTHER CHARACTERS: Most other characters are largely ignored or excluded from the fanfiction world, except maybe Kaede to say something helpful, or Kilala/Kirara to transport. But there do exist fanfictions that include various minor characters, including ones that have been killed off. There are even pairings of characters that have never met and were each killed off - YuraXHiten is one example.
Wow, I forgot Koga.
KOGA: Also spelled Kouga. Scottish/Australian. Has publicly, loudly, and often expressed his love for Kagome. So he must be in love with Inuyasha, obviously.
HAKKAKU AND GINTA: Who?
PLOT: The plot is to collect all the shikon jewel shards to complete the jewel, and kill off Naraku. This plot only exists in a few shadowy fanfictions. Find 'em if you can.