Xingyun

Xingyun is the slash ship between Xingqiu and Chongyun from the Genshin Impact fandom.

Canon
In Chongyun's voiceover lines, he states that he admires Xingqiu for his devotion to chivalry and passion for reading, but has also seen the latter's mean side. He is a common victim of Xingqiu's pranks and antics.

In Chongyun's story, it's stated that Xingqiu gave him the idea that, instead of attempting to reduce the effectiveness of his congenital positivity, he should search for an evil spirit that is immune to it. Xingqiu often gives him fake intel of sightings of evil spirits, and they come home empty-handed. Chongyun has no idea and blames it on his bad luck. Surprisingly, Xingqiu will try to lift his spirits after his pranks, doing things like getting him cold food.

In Xingqiu's voiceover lines, he states that he and Chongyun understand each other very well, implying they have been friends for a while. He also states that whenever you see Xiangling out and about searching for ingredients, she'll try to get you to try her newest recipe. He says that he'll usually get Chongyun to try it out.

In Xingqiu's story, it's stated that Chongyun is the one who usually bears the brunt of his bizarre humor. Just like in Chongyun's story, it talks about how he often pranks the latter by giving him fake intel, setting up traps in areas Chongyun practices in, etc.

In Xiangling's voiceover lines, she states that she always sees Xingqiu and Chongyun eating together at Wanmin Restaurant.

They are one, if not the only, ship who exhibits friendly, buddy-buddy interactions as stated by their stories/voicelines and Xiangling. They are also featured together in official arts. They speak highly of each other and in a fond manner as well, showcasing just how close of friends they are. Xingqiu is known to endlessly tease and pull pranks on Chongyun (making him eat spicy food, tricking him onto fake leads, etc) though tries his best to seem innocent, and sometimes even going as far to encouraging Chongyun and buying him cold desserts. Despite all this, Chongyun still refers to Xingqiu as a fine and true friend.

Fanon
The ship mainly sailed due to the popularity of the "Best Friends to Lovers" trope, and their dynamic. They are featured in each other's stories, and are introduced as close friends, much to a lot of shippers' joy. They are also exceedingly similar, both being strong, coming from influential families, seemingly not much at first sight, but having a more wild underside; they compliment each other nicely. Even outside character, Xiangliang, says she sees them dining together and in the official artworks, they are often together.

In-game, many users enjoy their elemental chemistry; as Xingqiu is a Hydro user and Chongyun is a Cryo user, both use elements that work very well with each other and are able to apply the "Frozen" debuff on enemies when working together.

Many people are fond of this ship as, unlike others, they have a canon foundation as being best friends. Additionally, due to neither of them having any confirmed love interests, or much interactions with the other characters in general, this ship is very popular nonetheless.

Fandom
FAN FICTION

Quotes
"Chongyun has had the privilege of meeting a true friend in his long journey as an exorcist: Xingqiu . . .

If Xingqiu has time to spare when such an occasion arises, he will encourage Chongyun, treat him to some new cold dish that he has found and then set off to get Chongyun's swindled money back.

''A warm and reliable companion indeed! — So Chongyun thinks at such moments. Who could he possibly trust, if not his fine friend Xingqiu?"'' - Chongyun's Story 4

"I do admire Xingqiu for his devotion to chivalry and his martial arts proficiency. However, I must warn you that he definitely has a mean side too. If you find that you fall foul of any of his antics, come to me and we'll form a "Victims of Xingqiu" alliance. There is strength in numbers." - Chongyun's voiceline about Xingqiu.

"While quiet and unassuming in front of strangers, he is gregarious and chatty in the company of close friends and family. Though more restrained than his elder brother, he even has a playful and mischievous side.

The one who usually bears the brunt of his bizarre sense of humor is someone named Chongyun, an exorcist usually found on one of the forest trails around Liyue." - Xingqiu's Story 4

"Ah, dear Chongyun. Though he understands me quite well, one has to exercise caution when teaming up with him to go on a quest. He is making good progress in the martial arts, but I would say he hasn't quite internalized the chivalric code yet... He needs more practice. Especially at eating spicy food." - Xingqiu's voiceline about Chongyun.

"... I usually get Chongyun to handle these situations, hehe..." - Xingqiu referring to Xiangling's new dishes.

"Chongyun? I always see him on his way to eat at Wanmin Restaurant with Xingqiu... Ah... or perhaps I should say I see him being dragged there by Xingqiu? Chongyun doesn't eat hot food. Every time the hot food arrives, Xingqiu politely apologizes and proceeds to try every dish. I just wanna dig in with him! The look on Chongyun's face is priceless. They're quite interesting, those two." - Xiangling's voiceline about Chongyun.

Trivia

 * Xingqiu calls Chongyun "my dear".
 * Chongyun tries to form a "Victims of Xingqiu" alliance with the Traveler.