It is not limited to humans. Loneliness is what those with a heart feel. You may reject it as weakness and push it away, deny it even. I do not mind.

[He lays his head on Urizen's shoulder, radiating smugness but also reaching to twine his fingers with Urizen's. Quite relaxed for being in a big bad Demon King's lap.]

As I said. I will not let you be lonely. Any part of you.