Board Thread:General Discussion/@comment-34798955-20180310144518/@comment-32182236-20190427213401

Chara only sees us as our partner because we and them share a goal:Eradicating everyone. And as Chara betrays us at the end of Genocide, it's not that they trust us, they're just using us to get what they want. There's no doubt that Chara at this point firmly believes that it's kill or be killed, and to see Frisk doing just that?

They're helping Frisk kill because they want to kill. But they need Frisk to kill enough to they can gain enough power to physically manifest.

But Chara doesn't consider you as their equal. After all, since when were YOU the one in control?

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As for why Chara would hate monsters because of Asriel's betrayal, that's the thing. Chara's main character flaw is hatred. They start hating things WAY too quickly. And hey, their hatred is reinforced by Toriel apparently replacing Chara with another human, which is one of the first things we see happen, and thus, one of the first things Chara sees happen after they awaken, likely still really angry about the whole betrayal. Plus, they're SOULless, so no feelings of compassion are going to kick in to steer them in the right direction. Put all that together, and you have a deadly combination.