C&C Vol. 34 DeathNote series Book 4 (part 1) the faith of Misa Amane − アフィリエイト動画まとめ

Someone else seems to have a death Note. Their even able to do more than Kira. Is this a potential threat or beneficial ally?

Death Not Book 3 part 2:
https://youtu.be/pfOdpnDE3-g