Ryougi Shiki

The protagonist of Kara no Kyoukai. Able to see lines of death, just like Tohno Shiki.
The last name “Ryougi” and first name “Shiki” both have an appropriate meaning. Consequently as a user of the mystic eyes of death perception it can be said she is several ranks higher than Tohno Shiki.
Tohno Shiki is pretty much her polar opposite. In fact, his personality is actually close to Kokutou Mikiya's.
If you called her Tohno Shiki's prototype, I wouldn't know how to answer.
Because, even though as a completed work Kara no Kyoukai predates Tsukihime by two years, I had the idea for Tsukihime first.
However, at the time the idea refused to become a story, so I stored it away and came back to it later when I finally made Tsukihime for real.
Before that, though, I ended up making something completely different, only keeping the protagonist from the original idea. The resulting work was Kara no Kyoukai.
Geez, I never imagined I'd end up working with the same “lines of death” idea for three whole years…

Tsukihime Data Collection: Tsukihime Dictionary
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A girl in her late teens. One of the main characters of the story, possessing the characteristic of Yin. A killer who could not kill.
She used a coarse male speech pattern, and used Ore as her first person pronoun. She had a cold personality and appeared to care about nothing.
She had only worn kimono up to the age of 16, but due to the comment of her high school peers, she bought a leather jacket. After that, she began this strange getup of wearing a leather jacket over a kimono during winter.
Although it seemed that she was concerned about her attire, but really she did not care.
She just wore what she wanted, but the result was consistently “always kimono,” “laced-up boots or geta,” “…red leather jacket.”
Mean, heartless, and merciless, but occasionally she would react in a surprisingly feminine way. Like Mikiya said, it you want to compare her to an animal, it would be a rabbit or something like that.1
She was the second child of House Ryougi, who artificially induced dual personalities in their offspring. Due to her confirmed multiple personality, her brother was abandoned as the heir in favor of her.
Because she was aware of her abnormality since childhood, Ryougi hated people as well as herself. Although she developed a cold personality as a result, secretly she wished to experience a normal person's happiness.
…Ever since she encountered the materialization of that dream, her fate changed drastically.
She had a male personality known as “SHIKI,” but he was lost due to an accident. Subsequently she developed the ability to perceive Lines of Death. Was it a compensation, or was it a sequela of the accident?
After awakening from the coma, she did not have a realistic sense of living. Although in frustration she attempted to feel this sense of living through killing, due to various accidents and benevolent obstructions she never succeeded.
With a uncertain sense of living, this listless girl continued to come to Touko's office day in and day out.
By the way, Shiki's emotions towards people were quite animalistic.
Regardless of good or evil, Shiki first divided people into “those she can be with” and “those she cannot be with.”
For those “she can be with,” she would stay with them even if she hated them. Touko was “dislike,” Azaka was “like,” such were the categories.
As to Mikiya, in the words of Shiki, “I don't know.”

Garden of sinners Pamphlet: Kara no Kyoukai Settings Glossary
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The protagonist of Kara no Kyoukai. Able to see lines of death, just like Tohno Shiki.
She wears a traditional kimono paired with a leather jacket and high-laced boots. Though she always carries a knife, her true talent is with the katana.
The last name “Ryougi” and first name “Shiki” both have an appropriate meaning. Consequently as a user of the mystic eyes of death perception it can be said she is several ranks higher than Tohno Shiki, who is pretty much her polar opposite. In fact, his personality is actually close to Kokutou Mikiya's.
For more details on this Shiki, please consult Kara no Kyoukai.

Tsukihime Dokuhon Plus Period: Tsukihime Dictionary Revised
Translator's Notes
  1. ^ A mean, heartless and merciless bunny.