Alright, here's a crazy theory. We know Karkat's a mutated lime blood, and that they have a supposed ability to calm the rage of the high bloods (Karkat's paps+shooshes) and now all of the lime bloods are extinct. Do you think the sopor slime pies are possibly made from the blood of lime bloods?

Sopor Slime is a calming agent, so it’s possible. But it’s unlikely given how the Lime Bloods have been extinct for a while and blood does go bad