I don't know about "probably", I'm just giving my two cents.
Until more is revealed about the Hell Devil I don't know for sure it's on Earth, just considering how it keeps manifesting on Earth I assume it lives there.
No Chainsaw Man thread
if we're to believe master WASN'T a devil from the start and actually the santa clause they referred to, then maybe the big thing was turning her into a devil she was contracted with? that'd be a pretty big power move honestly if thats the case, to become a devil. that would stand to reason however, why she didn't just get a devils heart instead of actually just becoming one?
POWER
PRINZipality
CheruBEAM
ANGEL
You have been warned
Wouldn't it be funny if they left Kobeni in hell and after some time skip she managed to came back with powerful devil contract and save the day?
No
kek
it would be funnier if she died
And I highly doubt she wasn't, just because she shows no reaction to pain does not mean in any way that she was in a good position or is completely untouchable by the strongest devils. She turned tail and ran like a bitch for a reason, because she was about to get utterly slaughtered, and now she needs Denji's help to defend her from a threat powered by a minute fraction of the thing you think is no threat to Makima. These last few chapters have been very telling as to what she's capable of and it's far from godlike.
There should be an angel counterpart to devils. Supernatural beings that get stronger the more they are worshipped.