It was the Taisho Era, Muichiro was about to leave to sell some coal, but his siblings were telling that they wanted to come, but then their mother came and told the siblings to not come, then Muichiro said goodbye before leaving to sell coal, then he walked away. After an hour of selling coal, Muichiro came back to his house he saw that his family was been killed

Muichiro: Shocked runs inside the house, the house were covered in blood, he saw that Yuichiro was still warm and breathing