naoku

Yes and do you know why it absorbs souls? Because Ragna/Bloodedge is the black beast

Ragna is Bloodedge. And not at the same time. Remember in calamity trigger how Ragna kept dying over and over and Rachel was talking about it always being the same. Thats cuz the Ragna we all no and stab is actually the 400 something Ragna. Takamagahara has actually ended the world a few times and "Rebooted it" and they tried to again at the end of calamity trigger but rachel pulled out the tsukiyomi unit and said FUCK YOU to stop it from being destroyed. and in a weird way Terumi is responsible for ragnas birth. and the sister that took care of Ragna, Jin, and Saya was actually Mercury "nines sister, kokonoe's aunt"

Actually your ALMOST correct. Ookami's effect is it cuts through anything magical IE ars magus. it also stops anything that heals people unnaturally. this includes - Hazama, Ragna, Rachel, and anything that heals in general. You could compare Ookami to like an ultimate nullifier

well its like this his sister Saya is being cloned over and over and being made into the prime field devices ie the Murokumos. If the Murokumos "unite" with Ragna they can become another black beast or a more powerful Murokumo

actually tager was an ikaruga ninja. thats why he gets flashes of memories from when he was human everytime he sees hazama and thats why bang seems so familiar to him. he died way after the church incident