Sigma x Reader

You're Nikolai's younger sister. A spitting image of him in terms of both appearance and behavior. You two are always side by side and share a habit of being equally annoying, always finding ways to irritate Sigma.
Sigma was your brother's best friend, and you never hesitated to annoy him just like your brother did. Despite the playful rivalry, your constant pranks and teasing secretly amused him, though he tried his best to hide it. The slight age difference between you was never a barrier to your antics, and you took every opportunity to make him laugh or roll his eyes in exasperation. Though, as time goes on, you realized that your harmless pranks have evolved into a crush, and you began to question your feelings for him. Was he aware of the extra effort you put into your pranks, hoping to impress him?
The line between friendship and something more had blurred, leaving you confused and uncertain about your feelings.

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