AYRT. I love this idea so much. Like, as a birthday treat or something (and after a week of being good and acknowledging his own goodness because hey, this stuff has to be earned), Frank asks Matt if he owns anything like a cane. Once a year, Frank can just about manage it, and it turns out that Matt likes the anticipation as much as the slap itself anyway so he spends like four hours talking dirty to him and trailing the damn thing over every inch of Matt he can reach. He only ends up giving him ten and Matt's blissed out of his mind.

Incredibly angsty aftercare with a massive slab of dom drop probaby not optional, and Frank feels like hell for days afterwards.