UGH. A part of me wants to just write a whole essay on this, but anyway.
Aden is trying to take over as Lord of the Midwest, after Lucas killed Klemens for starting shit with him. Lucas doesn't want to take over that territory, and Aden is one of his favorite subjects, so Lucas (and Raphael) support Aden's bid to take over the Midwest.
But Aden is like SUPER misogynistic. He hates women, although he's more than willing to engage in some BDSM with them (with him being dominant, of course). Aden's mother was stolen from Scotland and became a member of a Muslim guy's harem, and when Aden was 5, his mother had to allow him to be sold as a slave or leave the harem and support them both. She let him go. Aden ended up in a brothel as a male prostitute, and he thought his clients loved him (he was young), but one night he heard a female prostitute screaming and saved her from the guy who was beating her. In retaliation, his female madam allowed the asshole to whip the ever-loving shit out of Aden, like as often as he wanted. So every woman who Aden knew fucked him over, and he had no way to improve his life. When he was 27, he took a knife and slashed his madam's throat, and then a female vampire offered to turn him, and he was like "...sure, why not."
So Aden beds pretty women and likes to use lashes, whips, etc., along with some light, almost play bondage. And he seems to think women are below contempt.
Sidonie has reddish-gold hair, blue eyes, pale skin, and is the daughter of a newspaper publisher (EEEEEEEEEEEEEE). She's trying to expose sex slavery in Chicago, and when she gets too close, her source is killed by the slave traders. She finds out vampires are involved and wrangles an invitation to the big vampire lord gathering/kickoff to the "who wants to be Lord of the Midwest?" competition.
So Aden has to fight all the strong contenders to take over. He meets Sidonie at the gathering, and she wants to get close to him (in case he's involved or can give her leads on the whole slavery thing), and he's like "guess who I'm going to be whipping later," because have I mentioned he's an asshole? He totally is. She tells him that she's tracking down slave traders, and like the next night she's checking out a possible waypoint and is caught. One of Aden's vampires takes her to Aden, and then Aden and his guys storm in, kill the slave traders, and rescue the slaves.
Aden takes Sidonie to bed that night, which is like the second time they see each other, ripping her underwear in the process (seriously, girl, she didn't bring more so maybe tone it down a notch), and he is super bossy. Vampires can compel humans to obey them, and especially the first time a vampire is with a human, there's this element of "is there informed consent? 'cause I don't think there is" for me. The second time they go to bed, Aden ties her up (she figures out she can get out if she wants, but again, he didn't ask if that was okay, he just did it) and like barely uses any lube before he surprises her with anal sex, and she doesn't effing take any of his blood during that encounter, so:
-She didn't say she was okay with anal sex
-He totally didn't prepare her sufficiently for it
-Girl is going to be HURTING the next day
I get that the idea of an all-powerful, demanding man can be arousing, but if that had happened to me, I would have run away from that bastard. Nope. Nope nope nope. Of course Sidonie is still super attracted to him; she overhears him saying that he won't let "that woman" stand between him and what he wants, and she's like "noooooooooo" and gets all butthurt and runs, and of course Aden wasn't talking about her, he was talking about the only remaining vampire contender. And he goes after her, tells her that he wasn't talking about her, and she's like *swoon.*
The next day, while Aden is sleeping, Sidonie is kidnapped by humans and taken to the remaining vampire slave trader's house. Aden has to deal with the carnage (the kidnappers killed a bunch of his human daylight security force) and a challenge from the last remaining strong vampire, and he thinks Silas, that vampire, is behind Sidonie's kidnapping. But she isn't. Also, Aden's power is that he draws strength from the deaths of vampires. While they slaughter Silas's minions, Aden's just gaining power. It's odd and even he doesn't seem to like it.
Sid, in the meantime, still has her gun with her, but she's drugged and sleeps until the next night (convenient). Pinto, the vampire slave trader, comes in for her (he knows Aden's been with her) and then Aden comes in and slaughters the bad guys, and Sid empties her gun into Pinto's heart but Aden kills him. Then Aden's SUVs are blown up! Silas's human groupie did it 'cause he loved her (although she's dead). Aden's like "fuck this" and basically declares himself winner, come get your ass kicked if you think otherwise, and no one does. Then he takes Sid back to his place and they have sex, and she bites him and drinks blood (which lets her heal faster).
So Sid decides that Aden needs some sexual healing, involving her being dominant during sex (not in any dom/sub way, just her being on top), and Aden wants to roll her over and fuck her hard but lets her have control, and then it's like "yay I'm cured, all that bad shit I went through is done."
Sid and Aden go to South Dakota so Lucas can give Aden official control, and then they have an official gathering, and now Lucas and Katie are mated (super exciting for him), and Sid and Aden are in the process of being mated, I think (she tells him she'd rather have a diamond but this is cool too), and Sid and Aden are in love, and at least he isn't going to be smacking around random women now.
(I mean, Aden says that he knew how to inflict pain in ways that were pleasurable to his partners and would never force a woman, but considering how little he thought of them before, it just seems... eh. Kind of suspect. At least Sid is into it and is taking vampire blood, so she'll heal from his jackassery faster.)