[Pookie n Ta-ti]

What type of oil to use to soften up the black hard crust around her nipples to remove Black dirt..🤔.she keep licking the waxy stickiness and it turns dirty and Black....but it very hard to remove🤔....I peeled a little off and it did not seem to bother or PAIN her....it has to be an easier way to clean this off....PLEASE HELP....
I DID NOTICE IT CAME BACK AFTER AWHILE.....WHY IS THIS HAPPENING💯