"One hundred thousand Feather Coins a month is a decent sum for the former extra that you were, but with your ability to communicate with rodent species, earning that much is a breeze." Nevertheless, Jiang Shu didn't let his guard down, because the price of this transaction seemed too low.
He wondered if the Rat King Phil was intentionally setting the bar so low, or if his vision was just that limited. A monthly salary of one hundred thousand was an unimaginably huge amount to him.
But as Jiang Shu had mentioned, for a Wisdom Mutant with a power that defies common understanding, a mere one hundred thousand a month was minuscule.
Using rat soldiers to stealthily loot, to carry poison for secret assassinations, to establish an information trading organization, etc.
A little thought reveals many ways to make money. If Jiang Shu had this ability, he certainly wouldn't have ended up in such a situation.