Нахт

A Lost-Type Magical Heritage with a female personality whose physical form is that of the legendary blade, Dáinsleif. She is wielded by Haunted.

In her regular form, Nacht takes the shape of a twisted rapier with a skull by its handle. Her Hero Form armor is colored black and has fish-like motifs with fins and scales. In her human form, Nacht wears a black, goth-loli dress and had blue and blackish hair in a hime-cut style. Her eyes are particularly dark and iridescent, and gave off a villainous hue.

Nacht has a very flippant and critical personality who is constantly questioning Haunted's decision making but nonetheless decides to remain under his usage as she loved his corroded persona. She is very informal, most likely due to her extended time with her wielder, and very prideful of her abilities. Similar to Lapis, Nacht is very clingy and gets jealous if Haunted praises another blade.

(Source: Taimadou Gakuen 35 Wiki)