A strap system that runs under the seat of an ordinary chair and turns it into something else entirely. Cuffs at the wrists and ankles, anchored to a central span that sits out of sight beneath the frame.
Every strap adjusts, so it fits a dining chair, an office chair, an armchair — whatever is in the room. Nothing is fixed to the furniture and nothing is left behind: it goes on in under a minute and packs down just as fast.
Sei Mio's answer to the problem of bondage gear that only works in a bedroom.