Someday.
One day after Kenshin and Xiaoxun got married.
One day before Myojin Yahiko inherits the reverse blade.
One day when Himura Kenji was still a little kid, he already started to fight against his father.
There was a day before Sagara Sanosuke was still idle with nothing to do and had not caught up with Takahe E.
Without blood and sword, there is only one day of life.
Conception: