All this dabbling in the affairs of spirifers has attracted attention. A sleek, indeed plump, devil calls on you one evening at your lodgings. Lolling in your second-best chair, he makes you a smiling offer. Your own exceptional soul would fetch a handsome price: shall we say, 1000 Nevercold Brass Slivers?
It's stained now anyway. You surely won't get a better offer now. (unlocked with Stain on your soul 1 - you have 7;)
'What about this?'
Let the devil know about your little… addition, before you commit to anything. (unlocked with Possession of a Particular Personal Enhancement)