In the Book
In the Movie
Kiriya was trained each day by SGT Farrell and observes Rita fighting.
Cage is trained by Rita at the beginning of each loop.
Sgt Ferrell Bartolomé is Brazilian/Japanese and teaches Kiriya about Japanese culture and history. He is very devoted to he welfare of his troops. He trains Kiriya several hours each loop and allows him to fight along side Rita.
Master Sgt Farrell is Causasian. He has no effect on Cage's development as a soldier.
Rita and Kiriya stay in her quarters the night before the last battle.
Cage suggests sex is a way out of the loop, but Rita turns him down. He gets a single kiss shortly before their last confrontation with the Mimics.
Kiriya talks Shasta into trading Rita's spare battle axe for memory unit used to repair Rita's Jacket.
Cage does not use an axe in the movie.
Rita's main weapon is her 200 kilogram battle axe; uses it to cut through the Mimic's exoskeleton. She cordinates her ground attacks with air strikes; attacks by running amongst the surviving the Mimics and cutting them apart.
Rita is rarely shown using the axe, she is seen for the most part on the battle field being led around by Cage trying to find a way to escape.