I Dated the Lost Song. Blind Date Corporation, #18

Cadence gets a request from the Blind Date Corp to take on the position of surrogate. It seems her body is ideal for carrying a child for a hero who hasn't been seen in years. She signs the contract, submits to the poking and prodding, and when the DNA tells its tale, she confronts the fact that her long-lost-sister has a job at Z-Corp. Arcady ran away at seventeen and never gave a thought to the eleven-year-old Cadence that was left behind as an early activator in a family that hated actives.
Cadence is brought to a lovely home outside the city, where she can breathe free without the constant pressure of other people's energy. She meets her trainer and tries to focus on her new quiet life. It's too quiet. Leska works for Z-Corp in accounting. She pushes numbers and checks estimates all day long. When Cadence's baby daddy decides she needs a companion, he calls Leska, and she moves into the guesthouse.
Leska has some acrobatic hobbies, and the equipment was part of her contract. It is set up at a friendly neighbour's estate, and the baby daddy learns that she's an omega. He immediately sets out to find her some protective alphas, and then things spin out of Leska's control.