Two was always better than one. Allison knew that now that she had two partners to look after and who looked after her. There was nothing she felt like she couldn't do with them by her side.
Headcanons under the cut.
Allison loves to cook and bake and makes food for the three of them. She loves Italian and Chinese foods and is getting pretty good at making homemade pies
Malia loves to sit with her partners in silence and just feel the way they breathe and their heartbeats, her favourite time of day is right before they fall asleep
Scott always has one hand on at least one of his partners, if not both, he's very tactile
They work together like a well oiled machine, every piece working for the greater purpose, and nothing irrelevant or unused
All three of them spend the full moons together, Malia prefers to spend it full shifted and Scott absolutely needs to have his partners scents surrounding him. Allison loves being able to help them and provide safety for them
Allison tried to teach Malia archery once but it didn't end very well and now Malia is forbidden from touching Allison's bow
Allison loves to roughhouse with her partners and she finds it so much fun to wrestle with Malia as her partner will get all growly and giggley
All of these make perfect sense to me. SO... let me explain.
First of all, they're obviously a power couple. Like, I don't really need to explain that one. Alpha Scott and Allison as the Matriarch for the Argents, PLUS Malia, the extremely powerful werecoyote! It's very obvious that they're gonna take over the world.
If you think about it, it's basically canon. In a weird way. Like, after Allison's death, there's no world in which Scott stops loving her or thinking about her, so she's basically the unspoken third member to his later relationship with Malia. Allison shaped the way that Scott thinks about love and the way he approaches it, so in a way, Malia is falling for the version of Scott that emerged from his time with Allison.
Even in an AU where she lives, Allison has really entwined herself in Scott's life and who Scott is, so Malia would have to be comfortable enough with that to date Scott.
All three of them, though!
Allison and Malia don't interact in canon much at all. They know of each other, but there's very little connection. I feel that, if Allison lived, there would definitely be a bit of contention. I think Allison would try her best, but that there would still be a divide. Any connection is going to come up in conversation and in active battle. Malia would definitely admire Allison's strategic mind, though I can see it also being some contention, where Malia finds Allison's strategies too slow, wanting things to be complete as fast as possible. If they spoke in any sort of deep manner, they would realize just how similar they are.
They both have lots of pain and tragedy in their past, though Allison had more of a 'normal' life than Malia did.
Scott, on the other hand, is the kind of middle ground between their personalities. He's very steady but still has that very strong emotionality. He cares about everyone and everything. There's this sort of middle ground in terms of ability to wait- he wants to be able to strategise and wait, and learns that the more responsibility he takes on, but at first he's very impulsive and quick to move on things.
Moving on to my second point, Angst-factor. There's a lot of it there for them. For Allison, it's falling for not one, but two, of her family's 'natural enemies.' I feel like it's something so barely touched on in canon.
For Scott, it's very much going to be this angst in terms of emotional confusion. Poly relationships can very much be angsty at first, and I think Scott would fall into that self-loathing. He'd definitely feel terrible about having such strong feelings for both of them. He would really go in hard on himself, because I feel like he's such a self-loathing bitch. He'd feel greedy and as if he were cheating somehow, even if he's not dating one of them and harbouring feelings for the other or whatever. He'd definitely not be able to hold it in for too long.
Malia is probably going to have the least angst about the whole poly thing. For her, it's going to be anger and frustration because she still doesn't quite get why it's these people. Like, there's a level of distrust of Scott for pulling her out of her comfort zone (coyote form) and an obvious level of distrust for Allison for her family and her past. That's where the angst comes from.
Weirdos... Which is like duh. They're very weird. Allison, in being someone important to two weres, becomes very wolf-like. She suddenly becomes like a little instinctively wrong to humans, because she's using her body language to communicate with all the weres around her. It's so weird to watch her communicate with weres because she's using so few words, but her body is tilting and moving in ways humans don't during conversation.
Malia is both a weirdo in the human community and were community. Because she's a werecoyote, she's less likely to be scenting her partners or always touching them in the way that wolves would be. She's more likely to go hunting in coyote form and return with some sort of hunt for them. Malia is very independent, and I do think that she'd probably be doing her own thing a lot of the time and doesn't always seem like she's a part of the relationship to an outsider.
Scott is like duh. He's a weirdo. He's always scenting Allison, keeping her in his arms or close to him. He's always verbally claiming Malia as his, because he knows she doesn't like to be scented, but she does like still knowing that she belongs somewhere. He's also the Alpha in that he's always listening to his partner's feelings and thoughts, and he's always asking for their opinions in leading and stuff. It's not normal for Alphas to defer to their partners like Scott does.
This is so long already, but basically, I think they work together really well. I also think Malia works best in poly relationships and that this one is like really fuck yeah for her. Allison and Scott get to like nest and be domestic, and Malia gets to have people to come home to. <3 They're cuties to me.