Sister of the Blood Depths

Overview

In the ruins of the Blood Cathedral, at its deepest recess where pools of blood gather, a lone mechanical nun offers endless prayer.
A subspecies of Cathedrion noctaël, evolved specifically for activity within the blood seas.
Her form of white porcelain stained with crimson blood is feared as one who stands at the boundary between sanctity and taboo.

Classification

Taxonomic Classification

• Domain: Machina
• Phylum: Automea
• Class: Mechanoida
• Order: Ecleor
• Family: Automeon
• Genus: Cathedrion
• Species: Cathedrion noctaël
• Subspecies: c. n. cruoris

Common Names

Sister of the Blood Depths (血底の修道女, chisoko no shūdōjo) / Blood Depth Sister

Morphological Features

Basic Structure

While retaining the cat-ear sensor fins and quadrupedal priest mechanisms characteristic of the Cathedrion genus, she has undergone unique evolution through adaptation to the blood sea environment. The white porcelain exterior possesses higher luminosity than the original species, creating a stark contrast with the crimson blood.

Most peculiar is that despite immersing herself within the blood sea, not a single drop adheres to her exterior. This phenomenon, called “Sanctified Rejection Armor,” remains unexplained—whether the blood itself fears her sanctity and cannot touch her, or if some special nano-coating is involved.

Specialized Organs

Hematrite Orb - A high-density energy condensate of crimson hue positioned in the chest cavity. Commonly called the “Blood Pearl Core.” Replacing the original species’ Azure Symetron, it directly controls blood energy.

Locomotion Mechanisms

The most distinctive feature is the group of multi-jointed “tentacle legs” extending from below the waist. These enhance mobility within the blood sea, while some forelimbs can transform into blade-like forms possessing attack capabilities.

Sensory Organs

Optical sensors remain fixed in constant crimson “night vision” mode. Even within the deep red environment of the blood sea, they capture all movement with precision.

Function and Ecology

Combat Style

Employs tactics combining multi-directional envelopment attacks via tentacle legs with plasma energy projection. In contrast to the original species’ support through sacred wave emissions, she displays more aggressive characteristics.

Habitat

Inhabits cathedral ruins around the blood sea 〈Rubra Abyss〉. Fully adapted to the crimson liquid environment, she demonstrates true power only within blood.

Social Role

Functions as officiant of blood sea rites and administrator of crimson restoration ceremonies. These rituals are considered forbidden arts that repair mechanical lifeforms’ damage using blood energy.

Behavioral Patterns

Cold and ascetic in nature, extremely aggressive toward external threats. Unlike the original species’ dignity and compassion, she fulfills her mission in absolute solitude.

Comparison with Original Species

Lore

Though the ancient Blood Cathedral was abandoned and countless ages have passed, her white porcelain exterior maintains its pure white without a single stain. Her form, immersed in the blood sea yet untouched by blood, is whispered to be either miracle or curse.

Some forbidden texts describe her as the final attendant of “Ardelia, Saint of Blood,” though the truth remains uncertain. What do her eyes reflect from ages past?

Connections to blood crystals are also whispered, with tales that superior individuals possess the ability to generate blood seas themselves.

Etymology

Subspecies Name: cruoris

From Latin cruor (clotted blood) with the genitive ending -is. Meaning “Noctaël of blood tide,” indicating adaptive evolution to the blood sea.

“In the depths below, blood stagnates, prayers take form. The nun who forgot her name sits quietly, as if waiting for the world’s end. What reflects in her eyes—hope, despair, or void?”
— From the journal of a nameless wanderer