You are Anna, a young woman interviewing to be hired as a governess by minor nobility.
You wait for what seems like hours in your best dress. It is a paltry thing in contrast to the vast mansion around you, but you want to make your best impression. A Governess's life is hard, it will be physically demanding of you, you have no doubt, but the money will be worth it. Finally, you are called in from the antechamber to meet the family matriarch. Under her withering gaze, you are ordered to strip. You understand that this is part of the interview process. The matriarch sits down on a chair and examines every aspect of your body, first with her eyes, and then roughly with her hands. Her fingers run over your breasts, then your stomach, and finally your sex. She inserts a finger into you and begins thrusting it in and out. You let out soft sighs and do your best to retain your composure as she explores your most intimate areas. After seemingly a long time, she retracts her fingers. A long strand of your sticky grool trails along her finger. She tastes it and appears satisfied. "I was told you would be a good candidate. Your performance remains to be seen, but it appears the assessment of the academy is not out of line. We have dire need of a capable governess. The position has been vacant for days, and my daughter is... incapable of restraining herself. You understand what is required of you?" You nod. You were practically raised in the academy to be a governess. You spent your youth being educated on all the demands extreme pregnancy makes upon a woman's body, while you prepared yourself mentally and physically for the ordeal. You agreed to take the position at this house despite its infamous reputation among your trade: You would be required to deal with excessively horny noblewomen.
"Good." The matriarch stands up.
"You understand," she says, "That I have three daughters." You nod. "The eldest is a whore. The second is a queer tramp. And the third is agreeable, but, especially fertile. You will be contracted to provide your services for all three. Do you understand?"
You nod again. This is nothing new to you.
You are lead to the basement, where a contracted alchemist begins to procedure. The daughters are absent, but a sample of their blood is all that is required to proceed. The ritual is fairly mundane, you don't feel much at all really, but you know it is done. Their three wombs are bound to yours now. Whenever they would get pregnant, you will instead. You understand that you will likely be pregnant for the rest of your life, once it begins. It is not at all uncommon for a governess with a long career to bear hundreds, even thousands of children.
You take a moment to admire your flat stomach and below average bust, perhaps for the last time. You remind yourself to enjoy it now, before it's gone for good. Then, you think to the years of service ahead of you. You're a young woman with a promising future ahead of her. All you have to do is bear hundreds, even thousands of children for eccentric noble families.