World details:
Since every author seems to define their A/O world differently, I wanted to fill in some details before starting.
When the first pandemic hit, no one expected it to be the first of 5, or that the general population would end up mostly infertile. In time, fertility returned, but not to everyone.
Betas are the majority of the population, about 65%. They are as close to "average" as possible. They are neither markedly aggressive nor submissive. Some beta couples can have children, others struggle. A beta female can be impregnated by an alpha male, often by a beta male, but a beta male cannot be impregnated by a beta female or an alpha female. Beta males can impregnate omega females, while beta females cannot.
Alphas are about 20-25% of the population. They are assertive, sometimes aggressive. Their high levels of testosterone make keeping their tempers in check a challenge. They also have health risks associated with high testosterone. Most of the sports stars, presidents/CEOs of major corporations, politicians, etc are alphas. Either gender alpha can impregnate female betas and omegas of any gender, but not other alphas or male betas. For alphas, an omega mate is both ideal and more responsibility than some want to take on. Bad alphas have been known to harm, rape, cheat on, and abandon their omegas, who are too delicate to handle it. Some abandoned omegas have been known to commit suicide.
Omegas are about 5-10% of the population. They are the breeder class and are intended to have children, but considered too rare and delicate to risk in battle, etc. Most work inside the home. They are submissive, timid, sensitive, and usually kind. They have higher levels of estrogen. Some have a difficult time caring for themselves, and when in heat are in immediate danger from any alpha who smells their heat, and betas who occasionally attack them. The only ways to avoid these dangers are to suppress their heats or by claimed by an alpha. They have been misused through history—raped, attacked, kidnapped into sex slavery, human trafficked, etc. They cannot impregnate anyone, but can be impregnated by alphas of either gender and beta males. They seek alpha mates, but are also cautious and self-protective. Omegas are never aggressive with the single exception of defending their young. Male omegas are sometimes victims of ridicule.
Maryse Lightwood glares at the picture in her hand. The lovely omega woman died years ago, but Maryse's dislike, once established, is for life. As an alpha woman, her reproductive life has been an experiment in humiliation. She could not conceive, carry, nor bear life. She could get an omega male pregnant; she was capable of having the right parts when needed, and not all female alphas were. Some alpha women had both male and female sex organs, and either would present when needed. But it did her no good.
Male omegas were harder to find, unclaimed ones virtually impossible. And submissive men made her queasy anyway. Sometimes alphas got together, more as a power couple than because of a desire to have children, and she longed for a man as strong as she was, stronger even. She supposed she could have claimed a female omega, but she had less than no sexual interest in women. Most women did nothing but talk and cry.
So she'd found Robert Lightwood, a beta she easily bossed around, got him involved in the Circle, and thought everything would be fine. But it hadn't been. Her world had fallen apart. The Circle was disbanded, Valentine forced into seclusion (oh Valentine, how she desperately had wanted that powerful all male alpha to desire her and fuck her senseless but he never had), the ringleaders put to death, she and so many others stripped of their duties, temporarily deruned, her career left in shambles.
Then she tried to move on and create a family with her husband. They found the woman in the picture to be their surrogate, but every time the doctors had taken an egg from Maryse's body and combined it with her husband's sperm, the doctors would implant the egg in the surrogate's uterus and it would die. Within days, hours, sometimes minutes. Maryse's eggs did not want live. Every one of them dead on contact.
Finally, it worked, and she was able to have two children with her husband. The doctors and her husband told her it had finally worked—twice—but she suspicious about whether Robert had simply slept with the other woman finally, exhausted from trying to get life out of a barren desert.
But now she was even more suspicious. She had expected her gifted son, tall, strong, fit, handsome beyond words, talented with the serif blade, so talented with a bow and arrow, when a person mentioned "The Archer" every Shadowhunter on earth knew who you were talking about, she had expected her pride and joy to quickly present as an alpha on his 16th birthday. But nothing happened. Literally. It wasn't terribly unusual for a young person to not be sexually mature enough to present at 16. It then usually happened at 18, or even 21.
Naturally her daughter, who had been sneaking out to meet guys already, presented easily and quickly at 16- as an alpha. Maryse was proud, but scared for Isabelle. She knew how hard the road could be for a female alpha. All because they weren't frilly girly girls. All because I value my career, she thinks, angrily.
But Alec...years went by, and at 25, it finally happened. She takes a deep breath. There has to be some way to hide this. But how at this point?! Every alpha at the Institute smelled a new omega coming into their first heat. Naturally everyone was questioning the female students and Shadowhunters first, but none of them were presenting. There would have been nothing she or her husband could do to stop alphas in rut from raping her son if she hadn't thought far enough to send him off the premises immediately. As it was, she had to get a special cleaning crew in to sanitize everything, especially his bedroom.
His heat had ended and he was coming back tomorrow. They'd given him an apartment they owned downtown, some food, books, and his phone, and left him there. A new omega in their first heat. Alone. But she hadn't known what else to do. Now she has a bottle of suppressants in her hand and a never-ending prescription. There isn't any reason he needs to have heats at all- no reason he needs to be in pain and no reason she needs to be embarrassed. No one would know. Alec could pass for beta, hell he could pass for alpha half the time, though now she's remembering all the times Alec had backed away from a confrontation and let his sister handle it.
Her tall, tough, strong, magnetic son was an omega. A male omega. Isabelle is mine, she thinks, but Alec might be that other woman's. She looks again at the picture of the woman she detests, whether it's because she hates submissive people, or simply hates anyone who can do something she can't.
Alexander was always going to be the strong dominant alpha male she so longed for but couldn't have. He'd placate her desire for male dominance, something her husband had never, even for one moment, been capable of expressing. He'd marry and give her grandchildren. But now she saw her dreams going up in smoke. She'll put him on suppressants permanently until they figure this out. In the meantime, they needed to put out subtle feelers with parents of alpha daughters who might find an omega son-in-law a tempting idea. She's heard Lydia Branwell was on her way to take over as Head of the New York Institute. She may be a perfect solution.