With the Homura Timestop + Sabrina Cleansing = Infinite Hax combo, I'm guessing it will turn out that either
A) Magical girls need to eat/sleep to keep their bodies alive even if they are liches, or
B) Homura's timestop will indeed count as "active magic" and cancel as soon as she's within Kirika's range, as speculated earlier, or
C) Having piles and piles of grief marbles lying around is a terrible idea,
simply because it's too OP otherwise. Oriko loses instantly as soon as Homura and Sabrina have reason to off her. Well, instantly from her perspective anyway.