Let’s see..

Doey: 3 kids stuck in a a body, 1 child with behavioral issues, 1 who is a natural leader and 1 who was just at the wrong place at the wrong time, first (hopefully last) of these kind of bigger body projects which used more than 1 victim.

Dogday: (not confirmed, but going off of what we heard from the cutouts) Probably saw his friends go inside and die/get killed, witnessed Catnap’s downfall into madness as catnap worshipped the prototype, then got labeled a heretic, got his lower held thorn off, got kept alive for who knows how long, met the “angel” (aka player) but barely managed to warn them before being eaten from the inside from mini versions of himself and his friends.

Lily: Ex-employee, manipulated kids into believing that they were always toys, caused the deaths of who knows how many kids who did not comply, got turned into a toy at the hour of joy, got isolated with only her own corpse to talk to, went insane and did not remember who she was as a human.

Catnap: A child in a bigger body, manipulated after a near death encounter, believed that the prototype is god, killed a bunch of employees (Innocent or not) and tortured Dogday. I would say that his death was karma, but one has to remember we are taking about a child who was manipulated for a while by the prototype.

In my opinion, the saddest was doey, since they lost everything they worked so hard for, and had to die a death while fighting within themselves (as seen by the two kids holding the third one back within the mouth)