For this achievement, you have to
1./ beat the game on brutal difficulty. Beating it on coward or savage will not be enough.
2./ Get all Jen's pics. in story and survival.
3./ Unlock and buy all skills.
4./ Listen to all dr. west gramaphones.
5./ Get S rank on all survival stages.
I just have one more S rank to get and this achievement is mine.. :) Really, its not that hard.