Nakime

Nakime is a mysterious Biwa Demon that dwells in the Dimensional Infinity Fortress. Actually she is a member of the Twelve Demon Moons, replacing Hantengu and holding the position of Upper Moon Four.

Personality
Overall, Nakime is depicted as a mysterious yet cold biwa player who doesn't speak a word unless it is absolutely necessary. Her emotions are never shown, and on the rarer occasions when she does speak, she is often straightforward and blunt, making her responses as short as possible.

Functional Recovery Training Arc
Nakime makes her debut within the Infinite Dimensional Fortress playing her biwa, summoning the Lower Moons for a meeting following Rui's death. She does not utter a word.

Red Light District Arc
Nakime - once again - plays her biwa and summons the Upper Moons to a meeting after Daki and Gyutaro's deaths.

When questioned by Akaza as to where Muzan Kibutsuji is, she replies straightforwardly that he has not yet arrived. She is also questioned as to where Upper Moon One is, to which she replies (after Akaza's and Doma's bout) that he has always been there; he was the first to arrive.

At the end of the meeting, Nakime plays her biwa again and bluntly refuses Doma's cut-off offer.

Pillar Training Arc
Nakime, now revealed as the new Upper Moon Four replacing Hantengu, is shown near Kibutsuji Muzan. Expressing her honor at Muzan's compliment, she uses her technique to locate the hunters along with Nezuko upon his orders.

Quotes

 * "I refuse." Chapter 99, page 9.
 * "I am very honored." Chapter 134, page 19.