Columbine

Eyes—the eyes are covered with a thin cross-shaped bandage. The conclusion is that she doesn't need eyes to see you. That was scary enough.
Hair and Halo: Long, black-pink hair, pulled back into two ponytails at the front and left loose at the back. The creepiest detail was the angel-like winged ornaments above the ears. They looked dried, lifeless, or metallic—something ancient rather than a simple accessory.
Clothing: A light, almost white or silvery dress, reminiscent of a tutu and mourning attire at the same time. Lace, ruffles, but cool tones. Nothing aggressive in the outfit—the perfect contrast to her reputation.
Neck and limbs: They noted her thin, almost porcelain neck and fragile body. She looked like a doll—lifeless, perfectly symmetrical, and frighteningly fragile. This heightened the fear: if such "fragility" was the third most common characteristic among killers, then her strength had nothing to do with physics.
· Pose and "aura": In concept art and animations, she either stood frozen like a statue or made strange, jerky movements, as if she had a different rhythm to life. Doll-like smoothness or a sudden stop without warning.

Summary of the visuals of that time:
You see before you an eyeless angel in a white dress, with dried wings at her temples. She smiles calmly, doesn't look at you, but you know for sure that if you get close, you won't return. Everyone feared not her weapon, but the fact that something wrong was living in this doll-like body.

To encounter her was to encounter something ancient, inhuman, and deadly, hidden behind the mask of a harmless girl. She couldn't stand having her peace interrupted, and she sought to torment people in various ways.

Tartaglia stated that he would be willing to fight any Harbinger superior to himself, but added, "...but not her... there's something wrong with her. You have to be very careful with her." This was the main trigger for fans—if Tartaglia is afraid, then there's a reason.
· The Wanderer (Scaramuccia): He directly warned the Traveler to stay away from her, describing the Soubrette as a heartless person who remains "equally stupid, ignorant and callous" in any situation.

Columbine was perceived as a quiet terror of the Fatui. She was a character spoken of in whispers. Her third rank spoke of godlike power, capable of challenging the Archon, but the nature of this power seemed twisted and terrifying even to assassins and spies.