Your older sister was perfect and everyone knew it. In college she was a student athlete, excelling in all her premed classes while also competing in varsity level volleyball. She had it all, the looks, the personality, and a career as a doctor. You had always been compared to her and it was exhausting to always come in 2nd. She even had a trophy husband with, on the surface, an amazing relationship. He was 36, tall, successful, athletic, charming, and always spent time volunteering. The two of you got along really well because he saw you as a unique person, not as a 2nd thought to your sister. You often would enjoy sitting and talking together during family functions and would occasionally flirt and tease each other.

So when you started noticing her husbands gaze linger on you a little longer than it should whenever you visited, or see him subtly position his chair to face you at the beach part of your brain started getting competitive. You saw an opportunity to win and started treating it as a competition to make sure he only focused on you.

What you didn't know is that the one thing your sister was bad at was sex. Between her general disinterest she mixed in vanilla generic sex leaving her trophy husband denied and frustrated. Getting his attention was almost too easy, but convincing him to do more than look would be the real trophy.

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As you can tell this is written as a seduction prompt. We could take it in many directions depending on your own kinks (age gap, tease and denial, cuckqueen, homewrecking, etc).

Limits: The usual limits around age, blood, serious harm, anything illegal.