kamperkiller: Quill-Weave got Katia a new "stealth top" for... reasons.

Tahrey: It's called a "Power Window". All the strongest adventuresses have one. It allows you to leverage the magical abilities contained in one's decolletage, or more precisely the region just below it. +5 to STL and EVD, and against all attacks both physical and magical, though only when fighting either gynaephilic or uncontrollably bitchy opponents.

Whatever you do, don't go trying to find someone to fill in the hole for you.