tried to kill Nezuko even though she didn't do anything wrong and Tanjirou kept telling her that she is his sister and she doesn't eat humans, this ain't it chief
"I have a dream, a dream that one day oni and humans can live together"
"bad boy you cant keep a demon lemme just kill that for you"
excuse me what the fuck
Also, why do those cutesy scene remind me so much of Nozaki-kun?
A of people wouldn't die. What shocking news?! This is a hole in the plot. But I'm sure they will make some excuse like: It is not everyone that can master this technique, no matter how much or how hard they train their bodies.
Its actually her sisters dream that shes trying to follow to keep the memory of her alive thats why tanjiro said "you smell like you're always angry" meaning she puts a fake smile on but her true feelings are of killing every demon.
Kouchou's sister dreamed of saving demons -> Kouchou's sister died trying to save a demon -> Kouchou is really mad and hates demons inside BUT ALSO Kouchou doesn't want her sister's legacy to be lost so she tries to be nice and save demons (but actually still hates them).