If CWM was a part of TWRM then I installed it. I never explicitly installed anything by that name though.
Edit: About a year ago I had installed all the stuff I needed to root the phone but after much tinker I finally soft-bricked it and had to do a factory reset. At that time I had TWRP installed so I could flash Roms and whatnot, I noticed ~4gigs was missing after I installed Xcom:EU but I've looked for any file pertaining to xcom to no avail. I updated the OS, at the time, in an attempt to get Android to somehow recognize the missing space, but again, no dice.
P.S. I'm sorry I didn't add this information earlier.