this is naga, invited along to help translate. dancing for men. then there's this man, kinoko hajime, one of the best known and respected practitioners, a master of shibari, the art of ropes, or beautiful knots, of what for lack of a better word we call bondage. so how big is the sadomasochistic community? how many people are active participants? >> translator: 100,000 people. >> a lot? >> a lot. >> this is shibari. translation, to bind. and to make things more confusing for those looking for a concise takeaway, a comfortable reaction to what sure as hell looks disturbing, tomika, who spends most of her time whipping, burning, and generally abusing men, enthusiastically reverses roles in her longtime relationship with hajime. it looks like a very delicate procedure. does it hurt? or does it feel good? >> translator: of course. but this pain change to the expressing. she said when she was tied up, no need to think. just leave it to -- she love it. ♪ >> performance art, craft, fetish, or compulsion. it's an old and shockingly omnipr