- Oka yoshi and Zoku ki could have master immunity to being beheaded, and regenerate their heads, but they gave up and basically challenge Kagaya
- Yuichiro had the chance to go to heaven but instead choose hell, because there was nothing there in heaven for him, not his parents nor his brother nor Amane
- Amane never knew how to live with herself, she killed her children, her husband became a demon, she lost everything, it got to the point where she tried to kill herself
- Tanjiro tried to persuade Yuichiro to not die because he was the only one who could keep Amane's memory alive forever, but Yuichiro didn't knew what was the point, Why remember her forever? Why live an eternity of misery and loneliness? To remember a woman that no one will ever know who she is and all the sacrifices she has done? The demon slayer corps is already a secret and as time pass by nobody will know they ever existed to begin with, they'll became a fairytale that will eventually get lost in the air, So why should he rememberer?
- Sometimes Yuichiro saw his family in Amane and Amane saw her children in Yuichiro
- Zoku ki is all alone in hell with his father because he refused to let his siblings and mom go to hell with him
- Shi ane always hated Zoku ki because he always ramble about how she doomed her sister, but now she understands he was always right
- many of the demons loved ones left heaven and went right to hell as soon as they died
- Mei gyo is alone because his orphans became scared of him
- Tanjiro didn't understood that his family was death until he almost attack someone at the red light district and when he understood what he did he started to had a mental breakdown, he almost got his sister and innocent people who have done a lot for him and Nezuko killed
- Inosuke was scared of his feelings for Tanjiro because even if he was different from the other demons it didn't change the fact he and everyone in the ice mansion hated them, they took the people they most loved not to mention they were breaking the rules and they're consider criminals for many people, he felt like it was better to hide it which made Tanjiro feel sad because he thought Inosuke didn't liked him back
