Bio

Name: ??? (Before reincarnated)/ Griseo Altrea (now)

Age: 15 (past)/ 18 (Now)

Race: Human (Former)/ Neutral spirit (now)

E/c: Purple

H/c: Light blue

Personality: Straight to the point, Creative, Protective over her relatives, Patient, Can get annoyed easily, Curious, and cares for those close to her.

Likes: Painting, Planetary observation, Astronomic observations, her little sister, Origami, Vegetables, Sometimes meat, Drawing, Gallery, Teaching people to draw,

Dislikes: Being disturbed while painting, Rain, Little sister getting hurt, AST, DEM, Kotori keep trying to make Shido date her, 

Spirit code name: Stellar/Star

Spirit Rank: [Unidentified due to being passive]

Relative:
Mom (Dead)
Father (Dead)
Astrae Altrea (Little sister) 
??? (Mother figure)
Miku Izayoi (Step-sister)

Look (former): [Unknown]

Look (Now): 

Long, light blue hair—almost an aqua shade—flowed down her back, with a few loose strands framing her face. A navy ribbon and a gold crescent-shaped ornament sat atop her head, with a delicate butterfly accent woven into the design. Her eyes were a deep, gem-like purple, standing out sharply against her pale complexion.

She wore a white and navy outfit, fitted yet flowing, with celestial patterns decorating the fabric. Gold star-shaped clasp resting on her chest.

Long, elegant white socks reached up to her knees, paired with shoes of the same color, completing the refined look. A set of white gloves adorned her hands, loose at the openings, with a gauntlet-like fabric covering half her arm, secured with gold details and navy straps. Her shoulders remained exposed, revealing her snow-white skin.

Love interest: Mukuro, Mayuri, Origami.

Backstory: [Data not found]

Little Sister Bio

Name: Astrae Altrea

A/n: I had to name her little sister not griseo since it will confuse people. 

Age: 15

Race: Neutral spirit

E/c: Purple

H/c: Light blue

Personality: Shy, A bit loner, careful, Will help her older sister if she can, creative, not talkative but if asked about her painting she is talkative and clingy to her older sister.

Likes: Painting, Her older sister, Origami, Painting with older sister, Art gallery, Mayuri, Mukuro, Being alone and not disturbed when painting, 

Dislikes: Being disturbed while painting, Rain, Big sister getting hurt, AST, DEM, Kotori keep trying to make Shido date her older sister and herself, Some Vegetables, Coffee, Sour things

Spirit Codename: Artist

Spirit rank: [unidentified due to being passive]

Relative:
??? (childhood friend before she died and reincarnated)
Mom (deceased)
Father (Deceased)
Griseo Altrea (Older sister)
??? (mother figure)
Miku Izayoi (Older step-sister)

Look: 

A hair of the same sky-blue color as her big sister, the only difference being the length—hers was shorter, with a silken sheen and gentle waves curling slightly at the ends.

Small white flowers nestled in her hair, adding to her delicate appearance. Her large, violet eyes gleamed with a gem-like radiance, standing out against her fair, porcelain-like skin.

She wore a white, sleeveless dress with navy and blue floral accents, cinched at the waist with a ribbon and an ornate flower brooch. A dark choker with a small cross-shaped ornament rested against her neck, complementing the subtle lace trimmings along the dress. A single black armband wrapped around her upper arm, while elegant gloves, adorning the other.

Platonic relation ship: Yoshino,Mayuri, Mukuro, Origami

Inverse form for both Adult griseo and Small griseo

In their Inverse Forms, these twin Spirits radiate a malevolent yet elegant aura, their silver-white hair flowing unnaturally as if caught in an unseen storm of power. Their red eyes glow with a dangerous intensity, no longer just the gaze of warriors but the embodiment of calamity itself.

Their astral dresses have transformed into something darker and more ominous—an intricate fusion of battle armor and ceremonial attire, laced with razor-sharp edges and crimson sigils pulsating with cursed energy.

(Adult griseo scythe)

A scythe with a sleek black blade, its edges glowing in an eerie purple light. The handle is dark and jagged, shaped like it was forged from shadows themselves. A glowing purple chain wraps around it, looping from the base to the middle, as if waiting to bind something in its grasp. The overall design gives off a sinister yet mesmerizing presence, like a weapon wielded by a reaper from the void.

(Small griseo scythe)

A scythe with an elegant, almost ethereal design. Its curved blade glows with a soft blue and purple hue, crackling with faint streaks of lightning. The handle is deep midnight blue, adorned with crescent shapes and delicate bead-like ornaments that dangle like charms. Near the base, sharp silver accents and glowing orbs add to its mystical presence. The entire weapon feels less like a tool of destruction and more like a relic of a celestial being—graceful, deadly, and otherworldly.

Notes: In any case one of them goes inverse the other one will also go inverse after some time due to the connection they have together.

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Quick explanation:

Neutral spirits are different than the regular spirits in date a live, they have a very different type of sephira crystals. They could be influenced by a higher/stronger spirit from them, with the exception that the more they are influenced by the same spirit the more they will become resistant to the spirit's influence except for Mio Takamiya's influence due to her being the spirit of origin. 

When being influenced by Mio Takamiya, the neutral spirit's astral dress will be similar to her astral dress along with their appearance changed to be a bit more similar to hers. They will not be able to resist the influence of Mio Takamiya and mostly will be clingy to her.

In another case of neutral spirits being influenced by other higher/stronger spirits, they will be able to use some abilities of the spirit's angel that influence them. But the more they are influenced by the same spirit over and over again. They will become more resistant and have a chance to keep those abilities of the spirit's angel permanently and be able to use them immediately like how the spirits do it.