Apocalyptica - Part One is the first episode in a serialized novel.
Ran Lawson is having a bad day. Her boyfriend turns out to be a vindictive jerk bent on making her life hell, and as icing on the cake the apocalypse happens while she's trying to sort things out.
Thanks to a past she'd rather forget, Ran is ready to handle what comes next. Armed with an endless supply of facts (and an armory full of guns, obviously), she finds herself allied with a stranger and aimed at a singular goal: survive and help others do the same.