For a treasure like this, it isn't that he doesn't own any, but they are precious stocks kept at the bottom of the chest. Unless the injury is severe enough to be life-threatening, he usually hesitates to use it.
Moreover, in terms of medicinal efficacy, the ones in the hands of the Nine Hells Demon God are definitely better.
"Why are you the only one here? Where's Red Flame?" The Nine Hells Demon God waved a hand and asked casually, "Did he get delayed on the way, or is he hiding to heal from severe injuries?"
"My lord, Red Flame, he... he has fallen." The Black Feather Demon God lowered his head in shame, "Those few human True Immortals were too powerful. Red Flame got entangled and couldn't escape."
"What?!"
The face of the Nine Hells Demon God changed, instantly darkening.
The Red Flame Demon God was one of his most capable and trusted Demon Gods, and he actually perished at the hands of the human race?!
