Tohno Shiki

The protagonist. He is the kind of character that makes both friends and enemies without realizing it.
His habit of collecting edged weapons is probably a trait left over from the “other” Shiki, from Kara no Kyoukai. Taking his glasses off for every single event CG is his charm point.

Tsukihime Data Collection: Tsukihime Dictionary
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The main protagonist of Tsukihime. Formerly Nanaya Shiki. Originally born into a demon hunter family, but when his family was destroyed, he was taken in by the Tohno family. After a certain accident, Shiki was sent to live at the Arima household. The story of Tsukihime starts with Shiki being called back to live at the Tohno residence. In Melty Blood, there is a storyline where Miyako comes to take back her big bro. Despite being stereotypical… it doesn't feel wrong….

MB Official Strategy Guide: Melty Blood Glossary
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The protagonist of Tsukihime. Afflicted with chronic anemia. Mister Glasses.
He is the kind of character that makes both friends and enemies without realizing it. His habit of collecting edged weapons is probably a trait left over from the “other” Shiki, from Kara no Kyoukai. Taking his glasses off for every single event CG is his charm point.
An unfortunate boy, who suffered through various ordeals in Tsukihime, was dragged into strange situations in Kagetsu Tohya, and had a terrible time in Melty Blood.
Because he lived true to his promise with Aozaki Aoko to “become a man in the manner he thinks is right,” he developed into a good and upright person, but at his core he is actually comparatively cold-hearted. Or rather, no matter what happens, good or bad, he simply accepts it as it is. In a sense, this reckless way of life is similar to that of a hermit who has retired from society.

Tsukihime Dokuhon Plus Period: Tsukihime Dictionary Revised
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The protagonist of Tsukihime. He is an extraordinarily ordinary young man who possesses the mystic eyes of death perception.
Eight years ago (nine years ago counting from Melty Blood), he received a massive chest wound in a traffic accident, but miraculously revived. After recovering, however, he developed chronic anemia, and so was sent to live with the Arima family by his father Makihisa.
He is the kind of character that makes both friends and enemies without realizing it.
Because he lived true to his promise with Aozaki Aoko to “become a man in the manner he thinks is right,” he developed into a good and upright person. Perhaps because of his ability to see death all around him, he has a comparatively farsighted view of things. No matter what happens, he just takes it in stride. Que sera, sera.
A peculiar type of superhero who's basically benign, but if you approach him with the intent to cause him harm he'll destroy you.

MB Act Cadenza PS2 Manual: Tsukihime Dictionary