First off let me clarify some things so this ship won't sound like the most illegal thing you saw/heard.
between 1882 - 1912 is when this summary takes place. Everyone's ages will stay the same except of course Tanjirou and Nezuko (and the rest of the family if you want to count it)
Tanjirou will be 30 (since he has never unlocked the mark he never suffered from the curse of it) He masters the breath of the sun due to the spirit of Yoriichi lingering around the Kamado family. Speaking of the Kamado family they have all died when Tanjirou was 16 and of course except for Nezuko which you already know from there.
After escaping a slayer (not any hashira/pillar just a kinoe/rank 1 slayer) they travel the world to get revenge and turn Nezuko back to human.
Tanjirou later returns to his home to see his already buried family, praying he grabs his sword and runs back to Nezuko who is in a cave.
Nezuko will travel by box like normal.
After 5 years Tanjirou runs into Tamayo and Yuishiro. He had found her due to her smell but had also remembered that Yoriichi had told him about Tamayo.
After a brief confrontation and talking, Tanjirou and Tamayo alliance to create a cure to also defeat Muzan.
Also, Tanjirou is not a demon slayer due to fear is other slayers killing Nezuko when he gets missions.
During the age of 26, Tanjirou and Tamayo had formed a relationship (and yes Yuishiro was not happy, but slowly didn't mind it).
Tanjirou, Tamayo, Nezuko, and Yuishiro travel together with only Tanjirou (and maybe sometimes Yuishiro tags along) departing to get samples of blood. Tanjirou only departs whenever they made it to their stop, as to not get lost.
Is this ship weird? Yes, it's also the reason why I'm doing it.
This ship doesn't make sense. Yes, but anything can happen in fanfiction.
This is just for pure fun anyways so don't take it so seriously.
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(next day as I am too lazy to add to the stuff above, and also there were no good spots to put it.)
oh yeah and some other things.
Tanjirou still got his hair cut by the kinoe rank, but he later lets it grow back and put it in a ponytail.
They have set locations on a map on where their next settlement is.
Tanjirou had saved Kanae, but she had blacked out due to blood loss (so she only saw the silhouette of Tanjirou)
The story will begin after Tanjirou killed Rui with ease.
