Under normal circumstances, none of the parties involved in a trade would offer Souls of Death as compensation.
Souls of Death were not commonly used—other than by Beast Masters who had contracted with beings of the Undead Species, only those who wished to cultivate Evil Spirits required Souls of Death.
In this world, apart from Fang Mu, it was difficult to find others who dared to cultivate Evil Spirits.
The reason Fang Mu cultivated Evil Spirits was based on his ability to control them.
With absolute control over the Evil Spirits, all resources invested were worthwhile.
If someone else tried to cultivate Evil Spirits, they would have to be constantly wary of their retaliation.
Lang Huan wouldn't have mentioned Souls of Death for no reason; Fangmu Jianmu's identity did not include contracts with any Guardian Beasts of the Undead Species.
It seemed that Lang Huan must have learned some information.
