Jude!Watson's so sick and tired of RDJ!Holmes' chatter and violin playing that he finally snaps, tricking him into his handcuffs then gagging him. Once he has his attention, he explains why he's doing this and threatens to shove his violin bow where the sun don't shine (and given Holmes' unfortunate position and seeing that he's already taken drastic measures, our lovable detective doesn't doubt this and panicks at the possiblity). Watson sees the fear in his eyes and can't help but tease him by making him think he will actually do so, amusing himself by making and seeing him squirm. He doesn't release him til he's felt he's learned his lesson. So the doctor's kinda sadistic in this, but not so much where he's Dark!Watson and is OOC.
Oh, and sorry to be a downer but I wish for this to be strictly buddy buddy; no hanky panky, just two pals who're getting on each other's nerves.