"Absorb Manna, now!"
Ilya wasted no second heeding her words herself. h
Bacharoths also needed Manna for their exploits. There's no doubt that the Sorcerer's body, which had turned into dust, wasn't accompanied by Manna.
Hamel, the other Obelisk Sorcerer, and Commander Percival were right on time realizing what Ilya meant. Before the Bacharoth could steal the Manna once more, they were able to replenish their Manna reserve three times over.
Storing Manna in one's reserve for later use was not a skill that all Sorcerers could do. It wasn't dependent on their excellence but time. A Sorcerer had to train their bodies to absorb Manna sans using it immediately.
However, it wasn't the norm for Sorcerers who lived in places that are abundant with Manna.