Where does Torture Princess scale?

[ArgentDragonPluto]

So, I'm almost done reading Volume 4. The series is fantastic but I just realized, I have no clue how strong the characters are. From the top of my head I can say they are at least Small Building level by incinerating and freezing humans but at the same time these 10 demons are supposed to have the power of Diablo who should at least be Planet level, same goes for God of course. If the answer involves spoiler then would be great if it's marked since I still plan on reading rest of the volumes.

 

[ArgentDragonPluto]

So, I got a Small Building level result for a flesh monster when he fragmented a stone wall. Though it's a good feat, it would make everyone else at least Small Building level, which feels too weak.
Basically, the Flesh Monster has a fraction of the Knights power, and the Knight is the weakest of the 14 Demons who all have power from Diablo, a being capable of destroying the Planet.

So, is there a statement of the exact distribution of power? We know that Keiser is by far the strongest. Elisabeth can no diff all of the 13 Demons except for him. Asking to people who have read the series. With as little spoilers as possible since I'm on V4.