Sherumi and Menae

"Menae"

- I wonder why we can't go together...? But soon enough we'll understand... We're twins after all.

Menae and Sherumi are siblings that appeared in Distant Writings 1 and 2 (brief single-page explanations of Abyss characters that appeared at the end of chapters 39 & 40) and had a brief appearance in Made in Abyss Side Story Chapter 003. In Distant Writings 1, it is briefly explained that their conversation was located in the East District of Orth. Due to this, it is theorized that they were most likely born and raised in Orth.

Appearance
They are nearly identical twins with long thick hair and bangs that cover their forehead.

Personality
As twins, Menae and Sherumi seem to be very close to each other and interested in abyssal language.

Distant Writings 1
They discuss how tens of thousands of pictograms drawn on Abyssal Relics exist and how the simple ones were chosen and applied to the sounds of the official language which became the Abyssal Writings that they now currently use. They also talk about how each of the characters originally had "sounds" and "meanings" and were called Pictograms.

Distant Writings 2
They mention how Delvers use simplified versions of some of the Abyssal Writings characters as codes; there are two types of characters mentioned: "Netherglyphs: Abyssal Writings" (characters used regularly), and "Beyondglyphs: Distant Writings" (seemingly endless newly discovered characters). They also talk about a character unknown to them, "Ilblu" or "Iruburu", and wonder if the meaning of it would be known by the time they grow up.

Made in Abyss Side Story Chapter 003
After Jiruo's talk with Ozen about the Birthday-Death Disease and other various topics, Menae is suddenly shown talking to a deceased rotting Sherumi covered in flies in a dark room and wonders if Ozen would return again. After questioning why they can't go together, Menae stops talking and presumably dies. After this, a shot of Reg is shown where he sees nameplates fall from the sky; one of these nameplates say: "Sherumi returns to the Abyss".

Curse Fleet Arc
Sherumi and Menae run up to Nishagora's arms as she and Riko's party arrive at the Camp and are greeted by a member of Hail Hex and Srajo.

Riko's team are then to be tested in order to see if they can be trusted and whether they're the Shrine Maiden's scattered bait. They are to bring Nishagora down into the ground by any means necessary and Reg volunteers to do this alone while Nanachi assists in predicting moves while Riko prepares to blow her whistle. As they are fighting, Menae and Sherumi wonder whether they are themselves different from what Reg is, to which Srajo tells them to pay attention as he is not what they mean.

While Reg has been powered up by Riko blowing her whistle and Nishagora is now on the other side of taking a beating, Faputa notices that Srajo hands down the creature on her neck to Menae and Sherumi and is preparing to use her own whistle. Srajo then commands Menae and Sherumi to 'take the Waveproof Stance' and blows on her own whistle, powering up Nishagora similar to how Reg does, covering her in white fur.