Back in the Labyrinth, Sunny wasn't the only one who had killed countless Nightmare Creatures. In fact, due to his primary role as a scout, the three main fighters of the cohort had killed many more.
He knew for a fact that at least two of them — Effie and Caster — had fully saturated their soul cores long before their return journey was finished. Absorbing any more shards would have been useless for them. At some point, Nephis had begun to abstain from consuming her share of the spoils, too.
Added with the shards that Sunny traded for the unwanted Memories that the members of the cohort had accumulated, a truly incredible amount of the alluring crystals had been placed into Effie's leather bag.
He had often wondered what Nephis would use them for, and now, he had his answer.