User blog comment:AquilaeAltair/OnS Theories (S5). Sixth Theory - The method used to extract a demon/@comment-36009152-20190917022243

Noya being back is amazing… and no would not have seen that coming, less so him making a grisly grand entrance in the most creepiest manner, like this!

Mahiru-no-Yo was always a unique entity, there is some remembering of the Mahiru sides past (likely on account of the cross shaped dagger provided by Saito) that gives them an end plan in mind.

The Noya side, like Asurmaru and other demons likely has no memories on account of being a demon but he shows his influence when Mahiru-no-Yo collectively is encouraging Guren to partake in horrendous acts.

In true demon fashion, Mahiru-no-Yo is aware of how some things (like Guren stabbing Yu and others) can make Guren feel but feeling anything themselves they never act on it. Think it was all an act making a show of caring but was one effective method of pretending to with the goal of making Guren embrace all Mahiru-no-Yo's power.

Once Noya emerged it seems he was in a dormant state, he remembers Guren and quickly set about corrupting him again... with some idea time had passed so really do wonder what was going on in that state.

Still whilst Noya and Mahiru are two separate beings, which now apparently can be returned to what they were before (no clue what’s happened to Mahiru’s ghost or how Guren would react to Mahiru on her own) not certain if it is a case of Mahiru containing Noya as Mahiru-no-Yo. It’s like both of them disappear and a third being Mahiru-no-Yo takes their place, the only difference from a regular demon is some notion of a grand plan that does not involve taking them over fully (as of yet).

Guren throwing his sword into Mahiru-no-Yo’s chest could mean the heart is significant in removing a demon in certain circumstances. As for daggers would have to see what Mahiru is like, if she has a greater memory of what she wanted to do that she was alright being mixed with a demon, would like to see it!

Foreboding and all, more so with what Guren plans to do but overall it’s relieving. One persuasive all controlling demon can be resisted and split into it’s component parts, if that can be applied to Shikama Doji, great!

Like all of them, it’s a theory to enjoy reading, hope others add their views on an area where the more suggestions to remove demons (of the deity variety!) the better!