Seo Eun Hyuns Senses

"The criteria for dividing into the three major tribes is just one thing: [Vision].

The Heaven Tribe are those who find rituals suitable for their race, offer sacrifices to the heavens, and possess the eyes to read celestial energy. Our Human Race is included in this category.

The Earth Tribe are those who train their bodies, pushing physical limits to awaken certain senses, possessing the eyes to read the spiritual energy of the Earth. Mostly, the demons born from beasts make up the absolute majority.

And lastly, the Heart Tribe..."

"…The Heart Tribe, broadly speaking, refers to those capable of reading emotions and the very essence of sentient beings, their heart essence. By mastering what the Heaven Tribe and Earth Tribe call the Heart Path Method, they can perceive the colors of emotions and, furthermore, read minds themselves."

	-RToC Ch. 149-150, Heaven tribe stuff is standard cultivator divine sense consciousness stuff.
	Seo can't read minds but he does otherwise possess the vision of all three tribes.
	He can read Heart Essence though, which is just the summation of a person's vibe, for example:

While reading the Mad Lord's intent, I am able to glimpse his heart essence.

'Ugh...'

I silently mutter a chant upon sensing the darkness in his heart essence.

His heart essence is  a withered tree.

The blackened withered tree rooted in the darkness, without a single ray of light.

Only a thin, pinkish life force remains in the withered tree, barely supporting it, and it seems to collapse at any moment.

Each time the withered tree is about to fall, the madness in the Mad Lord's eyes seems to flare up.

The darkness and dampness felt from the withered tree, and its pain makes even me furrow my brows.

Although it’s less disgusting than the Bloodwood Practitioner, the dark despair is of a greater magnitude.

'Such a rotten heart.'

	-RToC Ch. 93