Hi Tania .My domme uses hot chili paste on my nipples after i have worn the bra with steel wool for 4 hours .My nipples are raw and tender and a spoonful of chili paste on each raw nipple burns worse than the fires of hell after 20 minutes I cant help but lose it because of the fire shooting through my tits .most times relief comes only after washing my nipples in ice water for half an hour .This is something which i receive only for serious breaches of discipline .I hope this helps your study >Best regards .Burning