Fear is one of all creature's most basic instincts.
Even those who are fearless, feel fear.
Bravery does not mean fearlessness, it means you can handle your own fears.
Agramon is not an entity - it is a feeling.
Agramon is all the gods of fear in all religions.
Its name is Fear, but he answers to all names mankind has put on the emotion.
Generally, it is formless. Agramon's pure appearance depends on the viewer's fears.
It can take physical forms too, but they are often distorted and hideous.
The only way for it to look 'normal' is through possessing a body.
This body is as mortal as any other, and it is not completely bound to it.
Much like The Darkness, from The Darkness (games and comics), Agramon can extend its being outside the possessed body.
Since Agramon is an emotion, standing in its presence will activate your adrenal glands to some extent.
Although, it's not truly evil, many hail Agramon as such - as they fear being afraid.
Agramon is an important piece of existence. Were it not for it, the world would crumble.
Fear is the only thing that keeps animals and beasts alive.
Would fear cease to exist, all of God's creation would tare itself apart.
Fear is the foundation stone in God's plan for all beings.
As Agramon is no longer an entity, one cannot kill him.
Although, would all things on earth vanish - or die - Agramon would simply shrink into nothingness.
Although being nothing but an emotion, Agramon has its own emotions too - which might seem contradictory.
It has its own goals, wants, and needs, which is why it interact with other gods and mortals.
Rules and reminders
Agramon's play style is, in a way, sort of poetic.
Agramon's writing can seem unconventional. It's never full (or whole) paragraphs, but more like fragmented paragraphs. But never one-liners.
Agramon can play with anyone, as long as they respect the lore behind its unconventional being.
Agramon itself is genderless, but it leans towards a masculine personality. But you can refer to it however you wish.