Where it all began, really.
Despite being one of Nasu's earliest written works, Witch on the Holy Night would not be released until after Fate/Extra CCC.
Written as a novel in the 1990s, Witch on the Holy Night was just too long for publishers at the time's liking. For that reason, after having built up an existing brand and fans, Nasu would end up releasing it in visual novel form, after some alteration.
Set in Misaki, Japan in 19, Witch on the Holy Night is the story of Aoko Aozaki and Soujyuro Sizuki.
A man of the mountains and the wildnerness.
Having There he meets Aoko Aozaki, the student council ---
Unbeknownst to Soujirou, his new schoolmate is not just different from what he is used to because --- but also because she is a mage.
Something he unknowingly witnesses one day, getting him involved in her business.
With little understanding of the 'normal' world to begin with, Soujirou finds himself stumbling into the world of the mages...