Solirus
Grossly Incandescent
oh good question, so Demons don't get stronger from eating other demons, since demons in this setting have an insance healing factor, and the more powerful the demon, the greater the healing capabilities can be. So no, demons can't eat other demons to get stronger, in fact, demons outside of the twelve moons tend to always avoid each other and fight even though they can't kill each other. The only demon that can kill a demon is Muzan, the first demon.
So apparently demons aren't nutritious enough.
So apparently demons aren't nutritious enough.