Work Text:
Mo Xuanyu was an only child right up until he suddenly wasn't. When he discovered his older siblings, he was quickly adopted not just by them, but also by the whole sprawling polycule his brothers were on either end of, plus all their associated friends and family. So in addition to two brothers and a sister, over the course of a few months, he gained a whole chaotic gaggle of bonus siblings-in-common-law who’d collectively decided he was their xiao di.
It was a lot, in an awesome way.
He will under no circumstances admit to having a favorite—Wei Wuxian would pout, and Da-ge would be sad—but secretly, it’s Nie Huaisang. They’re just endlessly cool, clever in a sneaky way, and so completely fucking fun to go shopping with, because they actually get his style.
“Is this too gay for a thesis defense, y'think?” Mo Xuanyu asks, looking in the mirror over his shoulder to check how the trousers of this suit fit his ass. It’s a deep burgundy color that he’s absolutely loving.
Nie Huaisang pokes their head out of their own dressing room and looks him over appraisingly. “I assume you’re planning to wear a shirt for the actual defense, not just that collar you’re passing off as a necklace, in which case, no, it looks the perfect amount of gay, xiao di.”
“Huaisang!” Mo Xuanyu sputters, whirling around to meet their amused, knowing look. “Who said anything about—”
“Well, if I wasn’t sure before, I definitely am now,” they laugh. Mo Xuanyu groans and blushes nearly as dark as the suit, and Nie Huaisang’s face softens. “He makes you happy?”
Mo Xuanyu runs his fingers over the metal links and smiles. “He really, really does, yeah.”
“Good,” Nie Huaisang declares, then fixes him with one of their truly chilling serious looks. “Because if he doesn’t, I’ll sic Da-ge on him. My Da-ge, not your Da-ge.”
Mo Xuanyu laughs at that. “My Da-ge isn’t exactly intimidating, no.”
“Not in the slightest,” Nie Huaisang agrees, cheerful again. “Now, let’s find you some shoes that say, 'Genius, and not the mad kind!’”
Yeah, Nie Huaisang is definitely Mo Xuanyu’s favorite bonus big sibling.