You face off against Crying Wolf during Act 4 (Shadow Moses). You must defeat her via non-lethal means.
I watched a video on Youtube describing how to drop her quickly with smoke grenades and stun grenades, but for some reason it didn't work for me.
Anyway, I found that using the mosin nagant was extremely useful.
Once you defeat her while she is in that awesome wolf mech armor suit, she does what every other lady of the BB corps does: drops her costume and requests a hug.
Obviously, don't give her one. Instead, turn around (literally 180') and you will see her doll next to a lock door. Run over and grab it, and this trophy is yours.
Questions, corrections and neg vote justifications below.