Lumither

Lumither is the family ship between Aether and Lumine from the Genshin Impact fandom.

Canon
At the beginning of the game, Aether and Lumine were separated by an unknown god. They've had little canon interaction since.

In the Prologue of the game "The Outlander Who Caught the Wind", The Knights of Favionus asked Aether/Lumine what reward they wanted for defeating Dvalin and saving Mondstadt, to which Aether/Lumine replied that they wanted Missing Person Posters put up around Mondstadt to look for their lost kin.

Later, Chapter I of the game "Farewell, Archaic Lord", Aether/Lumine repeated this sentiment, asking that Missing Person Posters be put up around Liyue Harbor. During the Lantern Rite Festival Event, Aether/Lumine made a wish for their respective sibling, stating "That's my sister's deepest desire." or "I really hope her wish will come true" if you picked Aether as the MC. If you picked Lumine as the MC, she'd say "That's my brother's deepest desire." or "I really hope his wish will come true".

Fanon
This ship isn't very popular as a het ship, due to the fact they have very little canon interaction. It has been widely disliked due to it's incestuous nature. There are few fan arts or comics/manga of a lover's relationship between them, but the ship was made more popularized through family-ship style media.

Fandom
FAN FICTION