In katanagatri the protag has a martial art that lets his body be a sword perfect for shirou

"My body is made of blades"
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I guess this fic was inspired by tainted steel,

I can honestly say I really want to see how this goes.

Excellent I am truly interested in see how you will make this Shirou surpass the base one, while he treads a different path.
~ Akumu, The Semi-Immortal Cat

I hope u will show his his origin awakening affected his behavior, also it’ll be cool if he can use some of the moves of Shichika from katanagatari considering that both of them are technically a sword

Good concept. As far as this initial chapter though, you need to add more detail to it especially to the characters. One, internal musing/emotions, helps build the mood if combined with the settings and situation, and two, if one would be faithful to Nasuverse canon, activate 'Anyone Can Die' mode. Sorry, this is Fate/Stay Night, not Tsukihime, meaning that you have Fate/Zero aftermath, sexualized worm problem, a priest having an orgy with a golden bastard, and cliche projectiles. Oh and no vampires to tank damage for the precious protagonist.

Interesting...

More please

Seems interesting. Curious to see where this'll go.

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So does he just cut things?

Is that really it?

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Okay.