Don't worry, Minque.

You haven't missed too much. We're still fighting off demons outside the cathedral, and we're all trying to head towards the cathedral in order to get some back-up (last time I checked) or at least some kind of sanctuary. Anyway, Jonacin and Celia glanced in, saw that maybe it wasn't a great idea, due to the fact that the back-up Knights are now undead, nasty zombies.

Jonacin is going in, and now he's calling us to back him up, since he's getting attacked by these Imperial zombies. Oh, and Sel has escaped the mage's place by going through some magical mirror.
Uh, that's it, basically at this point.
So, Serene should still be fighting somewhere outside...