I went back and read some earlier chapters. It seems Gallia is currently hanging out in the old resistance base, gradually killing and eating the members.
The "Deeply jealous god" is really a nuke, and the "ancient text" is either English or some cipher for the bomb codes... but then again, the world is in ruins... and it is pretty fantasy-based...
For how much though? I can imagine the body would start to decay... and if not, people would suspect something... so I guess if so, she just switches bodies or transforms...