Sub Poe explains D/s to Finn in detail and Finn is intrigued because some of it sounds really fun and he'd like to try and he likes to see Poe happy, so sure, he's on board. But Poe really really really wants to call Finn 'sir' while they're having sex and for some reason Finn has serious hangups about that (maybe he doesn't want to mix his sex life with any military stuff, given his background, or just doesn't completely understand why Poe wants it, or maybe something else? Maybe Poe just does it without thinking in the middle of sex and Finn panics a little? It's totally up to the author)

So they talk about it and come to a conclusion they're both comfortable with. Smut welcome but I'd love the focus of this to be on them talking.

(Prompt partly inspired by this really excellent fic http://archiveofourown.org/works/5822314)