DCOM: Enemy Within (XCOM x Girls Frontline) XCOM BUT GF

I thought my second chance at life was good, I mean I was able to become rich, Its the same world I was just in the past but around the same year I come back. ALIENS ATTACK! ACTUAL ALIENS, OH AND THEY'RE HELLBENT ON KILLING EVERYONE. At least I own part of GnK and the guy at the front owes me.
Now I need to figure out how to get back to my comfy life... hopefully in one piece and why are those girls holding specific rifles?