Board Thread:General Discussion/@comment-34798955-20180310144518/@comment-32182236-20190530183739

That was the start of a chain reaction. As I explained, Chara was also soulless, so their compassion couldn't kick in and bring them back into reason... Because it didn't exist anymore.

Toriel brought Frisk in as a child of her own, making it look like she just flat-out replaced Chara. Most monsters don't try to kill you (though some do), making it look like they still don't care about freedom. Toriel even flat-out says Asgore's plan shouldn't be allowed to succeed.

Having already been damaged by Asriel's betrayal, and no SOUL to help compassion kick in... It's going to lead to Chara to make the conclusion that Asriel wasn't just a special case. That the rest of the monsters are no better than Asriel. That ALL monsters are wrong.

What's the ONE monster that Chara describes positively? Undyne, the one monster who actually wants humanity's destruction. She's considered a hero by Chara. But, as Flowey explains to both us and Chara... In this world.. it's kill or be killed.