The discomfort didn't come from recording too many fire-attribute magical plants. Even if there was a limit to the Plant Compendium, he was sure he was still far from it.
There wasn't anything wrong with his body either.
The sudden discomfort came from his sixth sense, telling him something bad had happened or was going to happen in the near future to him or the people around him.
Vaan's Demigod-rank soul enabled him to perceive the laws, or rather, the 'beliefs' in the world. People's trust and belief in him was also a type of belief.
'Is this how divine-level beings sense the thoughts of their believers?' Vaan wondered.
He quickly comprehended that the cumulative belief of people in a divine-level being was also a form of power that could strengthen the said divine-level being.
The seven Great Devils relied on the connection formed through the power of belief with their worshippers.