User blog comment:Disfigure/Shalltear Bloodfallen's Bad End Battle w/a Certain Dragon Lord/@comment-33177490-20170910021929

"Her dress was in tatters, its remnants plastered to her body. However, the highest-grade items on Shalltear's body and the parts hidden by them were untouched."

I'm guessing that Shalltear must have fought the "???" Dragon Lord without equipping herself with the Valkyrie Armor, but kept using her default attire instead.