Combatants Will Be Dispatched!, Vol. 5 (light Novel)

In the week since Lilith arrived, the Demon Lord's army has seen significant losses, prompting an invitation to Six and the others for negotiations. But could the invite into demon territory be a trap?! ...Most likely. Also, whenever someone says the words "Demon Lord", the image of some evil old guy comes to mind. So who is this beautiful woman supposed to be?!