okay so I've watched a bit of underline and some other comics with Chara in them. Where they are kinda nice.

so I came up with this theory of how the timelines may of happened that may have made Chara not want to kill everyone.

please bear in mind I don't know everything about undertake so I may get some things wrong and spoilers.

okay so my theory starts off after the humans attacked asriel when he went to place Chara's body in Chara's home village.

When asriel went back and died Chara tried to reset to prevent Asriel but found they couldn't. Back then they didn't hate monsters.

Chara and Asriel where seperated so they spent many years alone. A bit like flowey where he developed the kill or be killed motto they developed a hatred for humans and monsters.

A few years later frisk fell.

At first frisk looked around and felt confused. Chara came up to frisk as a ghost and offered to help them escape. Unknown to frisk Chara was planning to use him/her as a way to destroy the world.

Frisk reluctantly agreed.

After meeting flowey frisk put more trust into Chara and was slightly doubtful of all monsters.

Thus the genocide route begins.

After the first few monster kills frisk became doubtful and asked chara if they could spare some monsters. Chara persuaded frisk that if they didn't kill them the monsters would kill them instead.

The genocide route continues and occasionally frisk would ask or beg for chara if they could spare some monsters. Each time Chara persuade frisk they were doing the right thing.

at the sans fight things were slightly different as Chara allowed frisk to spare him only to have sans betray them.

then chara finishes the job.

After they escape Chara destroys the world and frisk realizes the horrible mistake they made.

So after making a deal with Chara Frisk resets.

On there first reset frisk gets a neutral ending. Determined to free everyone Frisk resets and tries again. Chara watches in amusment as frisk resets over and over after each neutral ending.

Eventually Frisk frees everyone.

Some time later Chara tells frisk its time for frisk to uphold there end of the bargain and destroys everyone.

Frisk resets wanting to save her friends and Chara allows it though slightly confused as to why they cared so much.

Eventually on the third true ending she allows it to go on longer then the previous times. As it went on they slowly began to lose her hatred of monsters and very slowly their hatred of humans. She became friends with frisk.

and maybe possible alphys creates artificul souls so that she and asriel can come back. Maybe.

anyway what do you think of the theory?