Tony deliberately dawdled in stripping off, which he tried, unsuccessfully, to do provocatively.
Rufus needed Tony naked, not for anything sexual, but because it would be difficult to strip him later.
"You're taking far too long mister. I'll have to teach you a lesson!" Rufus really could act. "On the bed, NOW!" he bellowed.
In a flash, Tony was on his back, on the bed, hands and legs outstretched to be restrained. He also sported an erection. Rufus really didn't want to see that!
"Ready, doctor!"
Without handcuffs or ropes, Rufus had to improvise.
Ties and socks would work well.