It's a cheating au of some sort, published here in AFF written in full english. It was a CEO-office themed au where Winter (the boss) is heavily married, yet she finds Karina (her secretary) to be hot and so yeah they did the deed… that's all I can recall.   a few notes about this story that I can remember: Winter twirling the ring on her finger, to keep reminding herself that she's married. Karina keeps on riling Winter up, until they both finally give in.