While some humans seek Nirvana - in most Eastern religions this entails a discarding of the self, the ego; a reduction of self-awareness to the absolute minimum such that we cease to be aware of time, space, or our division from God and from other-things.
This is a pretty much neutral desire for people; neither Good nor evil; neither virtuous/ beautiful/ truthful - nor yet sinful/ ugly/ a lie. This is to say No to the self, but to say Yes to God. It is to wish for union with God.
But to be the devil or a demon is to refuse to yield-up consciousness, to hold fast to ego; yet to reject creation.
Such seek Anti-Nirvana = an eternal static-state of pure self, pure ego; to be the only known Being forever and everywhere. And this is Hell.
When the divine self is denied there is isolation.
It is the (shared, universal) divine self which makes possible love; because our real self has both our primordial individual self and God-within - inherited because we are God's Children.
It is this divine inheritance that enables us to love one another (as well as love God) - because we all share it.
Beings that have rejected God, hence the divine self, cannot love. They cannot love God; and also they cannot love one another. Since they have rejected God and Creation, they have also rejected the divine within them-selves.
Rejecting love; the devil and the demons can only relate to each other (and God) in terms of instrumentality; of being manipulative and exploitative.
To live in isolation in such an environment of exploitation is Hell.