Hello! she is in the new area, just outside Pistachio Village. There's a cabin in the woods. Her name is Margarita.
You must first recruit the "save stone" (she join to party after completing the first dungeon). Then, with the save stone in your party, you must go to Margarita. She will talk to you further and ask you for a "goblin soldier." Now you must recruit a goblin soldier, which costs 850 gold. Then, go back to Margarita.