Madame Von Bartlesby is Named Enemy in Borderlands 2. They are located in the Tundra Express region on the Planet Pandora. You encounter them during and after the side quest “You Are Cordially Invited: Party Prep” in the Skittering Mound area.
You can farm Madame Von Bartlesby for the Baby Maker as he is the dedicated loot source for this item. Madame Von Bartlesby’s legendary item has a 10% drop chance.