EiMiko

YaeBaal is the femslash ship between Yae Miko and Raiden Ei from the Genshin Impact fandom.

Canon
Yae Miko is stated to be an “old friend” of Baal and is one of her most trusted allies. Despite this, she does not support the Archon’s actions. Miko helps the traveler defeat Baal in order to save her from an eternity of solitude. They are shown to be very fond of each other and tease each other frequently.

Archon Quest
Yae Miko requests the traveler’s help in her plan to stop the Vision Hunt Decree. She asks them if they met the real Baal, whose name is Raiden Ei. Miko was formerly one of Ei’s followers, similar to what Dvalin is to Venti. She still cares deeply for her friend and wants to not only rid Inazuma of the Fatui, but save Ei in the process. Miko believes the reason Ei has not spoken to her is that the latter wants to eternally preserve their friendship as it was.

Miko enters the Plane of Euthymia and tells Ei that she shouldn’t forget who taught her how to create this space. Together, Miko and the traveler convince Ei to acknowledge the people of Inazuma’s ambitions. After the fight, Miko voices her concerns about Ei’s wellbeing. She tells Ei that the people of Inazuma don’t want the eternity that she is pursuing, and that she should give them her attention instead. Miko says that the loneliness Ei felt over the past five hundred years must have been unbearable. She comments that the environment becoming lighter around them is proof that Ei is happy to see her again. Miko teases Ei that she will have to spend the next several centuries updating her on everything that has happened. Ei laughs and says she never thought they’d meet again like this. She admits that seeing Miko again has been a very nice surprise. Miko asks if that means they are still friends, and Ei lightheartedly calls her childish.

Miko reveals that she traded the Electro gnosis to Scaramouche in exchange for the traveler’s life being spared. When asked why she had the gnosis, Miko replies that Ei entrusted it to her after cutting ties with Celestia. Miko then explains Ei’s past in detail to the traveler.

Imperatrix Umbrosa Chapter
Miko gives Ei time to think about what eternity means to her, and in the meantime assists the traveler in inviting Ei to see the outside world.

Quote
"Ah, that girl... She used to be the kind of person who could easily be swayed with some Fried Tofu. It's a relief to see how shrewd and resourceful she's now become. Still, I have to admit that I was a little upset to become the target of her scheming myself. I know it was for my own good, but I'm afraid she will mock me next time we meet... Perhaps I should take the initiative and strike her first? Hmm, she'll dodge it anyway."

- Ei's Voiceline about Miko

Fanon
The Yaebaal ship originated from the fandom’s theories about them. It became fairly popular among fan artists when Inazuma was released. The ship has grown even more after the 2.1 update revealed the truth about their relationship and had significant interactions between them. Currently there are 30+ Yaebaal fanfictions on Ao3. It is Baal’s second most popular ship after SaraBaal, and Yae Miko’s most popular.

Additionally, they both have Honkai Impact counterparts, which has made them popular among Honkai fans.

Fandom
FAN FICTION