Nana

Armor Valkyrie VII or Nana for short, is a magical entity previously known as "Armor Golem V7" named Nana by Nina. Along with Amelia, Nina and Sierra, she's one of the first slaves of Tooru's, presumed to be the fourth. She's 2 meters tall. Created for the purpose of exterminating the Divine Corpse Fragments, she was sent in from a different world along with her inactive power plant that has been sleeping for several thousand years in this world; Oruto considers her a sister. She lost the memory of her original mission and she was thought to be some ancient Armored Golem by Amelia’s group and taken in as a party member. By the way, even if she didn’t manage to obtain her very beautiful body Tooru was 100% serious about having "sex" with her and keeping his promise to her. As a result, he already researched in the Black Market of Paravata City for a "magical living product" that was capable of being equipped on a living being like an Armored Golem and attached as a sort of sex sleeve. The way she addresses Tooru is: Goshujin or (Master)