So flipping through the covers and previews for the rest of Death Metal it looks like Perpetua will play a very large role. This book was specd on here at CHU a year and a half ago.
Justice League annual #1 is Perpetua’s first full appearance prior we get a few mentions of her name starting in Justice League vol4 #8
So you can see this character is tied to Batman Who Laughs from the first mention of her name. Not a lot of copies of Justice League annual #1 out there for sale at the moment. When she destroys the whole DC universe like a Galactus, Black Winter, or Omnipotentis in Death Metal I imagine people will take notice and desperately seek this