There's always that one word that slips the mind of an individual, that one lost word that they'll search for maybe hours on end.
But... what if that word was truly lost, not just to a certain individual, but to the entire world for centuries to come? What would happen to the world itself, if one word was collectively lost by every person, ghost, youkai, god, demon, and script? Would the world collapse on itself, be at risk of being completely incinerated, or have the souls of dead and living alike stolen for the sake of reviving one person?
[In no way, shape, or form, do I claim Touhou Lost Word, or Touhou Project at all. This is just myself inserting an Oc into the place of the protagonist in Touhou LW. This story is not completely canon to the story of Touhou LW, and can only be updated as the game does in terms of story content. Also, there will be parts of this story that are not possible in the game. Please keep this disclaimer in mind.]
Kanda Kyoichi transmigrated to Konoha and became a temporary instructor at the Ninja Academy. Fortunately, he awakened the Mentor System.
By teaching others, he could earn rewards.
Thus began Kyoichi's career as a "teacher" in the ninja world.
Shisui: "Sensei's unique interpretation of the Will of Fire has given the Uchiha Clan a true sense of direction!"
Asuma: "The essence of the jade lies in protecting the people, with the advanced leading the way for the less experienced. Only then can Konoha become stronger!"
Kakashi: "He's my life mentor. He transformed Konoha!"
...
Years later, in the memoirs of Kyoichi, now the Hokage, he wrote:
"I honestly just wanted to be a life mentor!"