Tanjiro encounters Mist Hashira Muichiro Tokito and Kotetsu, a boy from the village, arguing. Muichiro is demanding that a "certain key" be handed over to him from Kotetsu. Being unable to look on in silence, Tanjiro intervenes to speak on behalf of Kotetsu, however Muichiro refuses to listen. According to Kotetsu, the key is used to operate a battle-type Mechanical Doll, Yoriichi Type Zero, that mimics the movement of a certain real-life swordsman...
After three days or so without water,
a human will seriously die.
،بعد حوالي ثلاثة أيّام بدون ماء
.قد يلقى أيّ إنسان حتفه
Bekommt er kein Wasser zu trinken,
stirbt ein Mensch bereits nach drei Tagen.
Pero la gente en serio se muere de sed
a los tres días.
Un ser humano muere
si pasa tres días sin beber.
N’importe quel humain
en mourrait après trois jours.
तीन दिन बिना पानी के,
पक्का इंसान मर जाएगा।
HYOTTOKO
Depois de três dias sem 
água, um humano morreria.
От жажды человек умирает
всего за три дня.