UNDERTALE/Chara

Overview
Chara is the first human to fall into the underground. While their life and death continue to haunt the Underground in a metaphorical sense, their spirit may also still be present in a more literal manner as well, depending on route and interpretation.

Apperance
Chara has the same sprite as the player, except that they wear a lime and yellow shirt and are light-skinned with a rosy blush. Their shirt is said to be the color negatives of the player's shirt colors, blue and purple. They are also seen to have a smile that contrasts the player's stoic expression.

Personality
Chara was perceived as a positive influence on the underground while alive, with other monsters claiming "the underground was filled with hope" when the Dreemurr family took them in. Asriel admits at the end of the pacifist route, however, that Chara "wasn't the greatest person." They are seen to be polite and deliberate at the end of the Genocide Route, thanking the player for guiding and reviving them. They opt to scare the player with a creepy face jumpscare if they decline to erase the world and take the reigns; they seem very fixated on the notion of people not being above consequences for their actions.

True Pacifist Route
They are never seen in-game, only mentioned by Asriel at the end of the game if you immediately go to where you started the game after the battle with Asriel. It is here where Asriel says that Chara "wasn't the greatest person." They are also depicted in flashbacks - the tapes in the true lab, the flashback to Asriel first meeting them after Frisk falls into the garbage dump in Waterfall, and in the game over screen (Which reflects Asgore's words to them on their deathbed).

Neutral Route
Once again, never seen in game. Only maybe mentioned by Asgore if Flowey was killed in a previous Neutral Route.

Genocide Route
At the end of the game, they will appear. They call the player a great person and say that the player's determination revived them. They then ask if the player wants to erase the world. They'll erase it regardless, refusing it only jumpscares you. Like in other routes, they depicted in the garbage dump flashback and the game over screen.

Trivia

 * Chara is the fallen human named at the beginning of the game. Naming them Chara prompts the text, "The true name."
 * Chara seems to be to be the one narrating things around Asgore's house in the Genocide Route - inspecting the mirror results in the text 'It's me, Chara' and they will describe one of the beds in Asgore's house as 'My bed.'
 * It is also very often speculated that they may be the one narrating on the other routes too; the Pacifist narrator makes dark and familiar jokes when examining Chara's bed and coffin.
 * Chara is also speculated to be the owner of the Worn Dagger and the Heart Locket, as they turn into the Real Knife and The Locket in the Genocide Route.
 * Chara died of buttercup poisoning.
 * It is speculated that this may be intentional on Chara's part, because in VHS tape 4, Asriel says that they would save the underground, and he was getting flowers.
 * They appear to have been inspired by an incident in which they and Asriel accidentally got Asgore sick by making him a pie using buttercups instead of butter, as seen in the True Lab VHS tapes.
 * Also, the monsters that tell Asriel's story at the end of the Neutral/Pacifist routes say that the human (Chara) became very ill.