Adonis
Apparently, the black flame was not harmful to Jason´s soul world core, rather it seemed that the black flame could purify his soul energy further. Also, the soul energy that was closest to the black flame looked more vibrant and shined brighter compared to the rest.
Thus, Jason tried to use his connection with the black flame to order it to move around and after a few motivating words, the flame slowly floated below the soul world core, purifying everything in the vicinity.
Jason nodded in satisfaction and decided to leave the soul world after checking how much soul energy he had accumulated and how far Artemis' evolution was.
It seemed like Artemis would evolve at the end of the week which was fine as his soul energy had surprisingly reached 15 units.
But, what Jason also noticed was that the black flame used up 0.01 units of his soul energy which was more than a little bit suspicious.