It wasn’t that Lu Yao didn’t notice dynamics; it was that he didn’t care.
One of the most profound side effects of his sister’s way of raising him was a well-honed sense of exactly how to act in accordance with an alpha’s commands without succumbing to the need to do it. In university it had served him well; Lu Yao had often stared down alphas who tried to challenge him after assuming that he was just a particularly late bloomer.
(University, too, had taught him how to avoid having an omega’s distress scent overly affect him. His heart could be tugged all it wanted, but Lu Yao was a man of logic, not emotion, and he refused to be moved by anything other than his own choice.
This trait, at least, his father approved of.)
In Shanghai, it meant that Bai Youning told him he had to accept her as his roommate and he laughed in her face.
(She was an alpha, child of an alpha, and Lu Yao had been raised among exactly that type of person. She had not known that yet.)
Lu Yao told her to get out, which she obviously didn’t do, but she also couldn’t find words to articulate how strange it was that he even could say that to her.
(Later, she would point to this as the first time she thought he might be interesting.)
In Shanghai, it also meant that when Lu Yao met the police inspector he didn’t do the double-take most people did upon realising that Qiao Chusheng was an omega.
Lu Yao had been abroad, and had seen many things that omegas could do when they had an army behind them. And Qiao Chusheng—for all his modestly-ducked head and politely acquiescing smile—certainly had that.
(That Lu Yao hadn’t been shocked by his dynamic meant Qiao Chusheng was interested in him. That Lu Yao didn’t seem to notice simply made him more intriguing still.)
Qiao Chusheng also knew how to start shit, a trait Lu Yao deeply appreciated and thought was underrated among omegas in general. Omegas who knew how to start shit could usually rely on a few seconds of alpha brains (and betas, sometimes, to a lesser extent) going ??? as they tried to understand that omegas can fight too.
(Lu Yao saw Qiao Chusheng practicing, one day, and realised that he’d started learning martial arts long before he’d presented; he just hadn’t stopped, the way many omegas did.)
Half the cases they solved together, Lu Yao made a leap of logic that the other detectives wouldn’t simply by ignoring standards of “Omegas don’t act like that,” because—as he often explained with a pointed glance at Qiao Chusheng—obviously they could.
(Less often, it was “Alphas don’t act like that,” because people accepted more things from alphas. Especially when the topic was murder. People didn’t like thinking about omegas murdering other people, even—as it so often was—for love.)
It took Lu Yao a month to realise he was the point both Bai Youning and Qiao Chusheng were orbiting, and another month to work up the courage to ask Qiao Chusheng (while they were both tipsy, at a bar after a case) if he’d ever done anything with Bai Youning.
Qiao Chusheng had laughed at him, and told him about how he’d been Bai Youning’s first crush, first obsession, first target of her rut. Then he’d said (more quietly, without meeting Lu Yao’s eyes) that he didn’t think it meant anything, anymore; he was still a symbol of the life Bai Youning was rejecting, even if they were working together on cases all the time.
Lu Yao thought there was something wrong with that logic, but then Qiao Chusheng had met his eyes with a bright smile and the same subtle omega charm that meant he always went home with girls. Even though Lu Yao could resist it, that didn’t always mean he wanted to.
(He had experimented, in university and Paris both, and learned that he didn’t care about dynamic or gender when it came to sex; he just needed to care about the person and wanted them to care about him. Qiao Chuseng certainly qualified.)
Of course, then he had to go home and deal with Bai Youning’s reaction to having Qiao Chusheng’s scent all over him, and that— Well.
Having an extremely attached alpha who didn’t want to admit her feelings about anyone growl posessively over both of them was not his idea of a good time.
(She did not jump him, which he’d been half afraid she would do. Instead, she stormed out in tears. Lu Yao thought he should feel worse about that than he did, but he couldn’t really work up emotions about this tactic when Bai Youning used it to end any argument she thought she was losing.)
Then Lu Yao’s family had started trying to steal him back home, because obviously he was hanging out with unworthy low-lifes, and things had gotten complicated.
Lu Yao had been wearing Qiao Chusheng’s watch for months, and letting both of them buy him food and whatever other gifts they felt like. Their money might be from unethical sources but if they wanted to spoil him, Lu Yao didn’t care. However, when Bai Youning marched into his room with a delicate collar, he finally balked.
“It doesn’t matter that it won’t have any effect on me,” he told her. “If you want to lay claim, find something like, well—” He raised his wrist and shook Qiao Chusheng’s watch at her. “Like this!”
She bared her teeth and stalked out.
The next day, a dozen silk ties and six bow-ties were laid out on the kitchen table. Lu Yao took this as the compromise it was, and felt Bai Youning’s satisfaction when he picked them up and switched one of his ties for one of hers.
From there, it only took an actual kidnapping for them to all start sleeping in the same bed.
(Lu Yao didn’t remember much of the actual kidnapping at first, but he did remember waking up with Bai Youning wrapped around him and Qiao Chusheng standing guard. Anyone who said that biology dictated actions, he thought hazily as he realised what was going on, should look at this scene and guess who the alpha, omega, and beta were; they were almost certain to be wrong.)
After that, Qiao Chusheng was over at their apartment more often than not when he wasn’t working. Not just for meals or to talk over cases, but to slip into bed with one or both of them. Qiao Chusheng would ask with his eyes and his body, not his voice, until Lu Yao loudly said, “My room or yours?” to Bai Youning and let her drag Qiao Chusheng along behind them to whichever bed she chose.
They didn’t talk about what it meant.
(It meant nothing. It meant everything. It was, itself, already the only acknowledgement they needed of what they were to each other.)
Their lives had already been intertwined, after all, their scents mingled to the point where nobody else could have claimed them if they’d tried.
Lu Yao smiled, and draped himself over his omega’s shoulders as his alpha asked impatient questions about their newest case. It didn’t matter if anyone else understood, or what words people gave to their relationship; they knew who they were to each other, and that was enough.
And sure, this life was nothing like what he’d expected, but that was because it was better than he ever could have dreamed.