
Wait, I’m confused. Who killed Shigure and why did he die because of Shiro? Why did Haru blamed himself for Shigure’s death. Sorry, please dumb it down for me. (/TДT)/

read the prequel and you'll find out in chapter 3 ! it's called MODS, here's a link
http://www.mangago.zone/read-manga/mods/
it's based around shiro's story instead though and it goes into detail about what happened to shigure

From what I understand:
1. He was told to see through drugs related trade by head of clan.
2. He felt devastated as it didn't sit well with Shigure's conscience. (His attitude changed which was noticed by Yukitaka and Haru.)
3. He cut his own finger (probably in meeting with -his father- head of clan). He wasn't kicked out, he cut his own finger and cut all ties with Yakuza.
4. Opened a Mahjong parlour and later took Shiro in & decided to leave the town with him.
5. (Now I say this but I got no proof, HE KNEW HE WAS GONNA DIE!) His last night he spend with Haru, he says 'there are more things he should have said to Haru' then there was blank black bubble (I think he said 'I love you').
This is how I think it went based on pieces we read. (Yagami from another clan later helps Haru after leaving Yakuza to open brothel.)
ISAAC YO MADAFAKA WHY SO COOL??!!! HE’S THE COOLEST OMEGA FITE ME!!!!
(๑•ㅂ•)و✧
Aaaaaand! Thank you uploader. No worries, everything is on track ╮( ̄▽ ̄)╭