Percival might be the director of the magical security department, all powerful and authoritative and cool and commanding when he's at his job, but in private he's incredibly submissive and is in an established relationship with his Dom, Newt Scamander.It's the only way he can function and remain sane after his captivity. Newt never beats him or punishes him, neither of them is into that. Newt is all about positive reinforcement, aka praise kink up the wazoo.
Meme link: http://fantasticbeasts-kinkmeme.dreamwidth.org/1184.html?thread=1814176#cmt1814176
Ao3 link: http://archiveofourown.org/works/9493484