This could be a lone story or the start of a serie, with increasing bondage but no sex themes.
Susan, a 35 years old woman with an athletic past who lives in a beautiful house with a pool, likes to be occasionally challenged to do escapes and dangerous stunts. Her daughters (Leia and Maria, 18 years old, who sometimes tie up themselves and each other) challenge her to do an escape for them.
Susan will be tied up in a swimsuit and more bondage will be added if she's not free in half an hour. She accepts.
If she can't escape in two hours, she'll have to accept more daring challenges in the future.
The daughters love her mother but Susan brags about her skills so they are annoyed, they want to win. They are clever and crafty, and will bend the rules to do nasty tricks to her.
If someone is interested in writing this please send me a message.