So, in this AU, Chara and Asriel did their plan but before they crossed the barrier, Toriel saw this and stopped them (In this AU, Toriel's mom was killed by humans so Toriel hates humans now). Toriel locked them up with Asgore in the ruins (Basically, Asgore's attitude is Toriel's). Toriel trained and trained over the years to fight and kill humans who fall. When Frisk falls down, (all the other fallen humans are dead) Asriel and Chara follow Frisk as they befriend all the monsters except Toriel. AT the end, they finally befriend Toriel and break the barrier with the souls and Chara's soul. Frisk gives Asriel and Chara half of their soul so Chara can survive. Why they're named Kai now is literally just because Chara didn't like to be called,"Asriel and Chara" so they agreed on the name,"Kai".
Flowey exists here but without the death of Asriel, this flowey is pure evil.
