Rose provided information about the layout of Big Shell and recorded Raiden's mission data, supporting Raiden in his infiltration. Rose also had a casual conversation with Raiden. She suggested to Raiden that the current date was the anniversary their first meeting. Raiden didn't remember this. Read more now on raiden shogun.
Rose investigated the death of Solid Snake to do a favor for Raiden and found that the body was interred and exhumed for DNA testing. Raiden was informed by Rose that the body had been identified as Solid Snake. However, the corpse was actually that of the clone Liquid Snake.
Rose reached out to Raiden when he was taken prisoner by the terrorist group Sons of Liberty in order to offer moral support. Rose learned his true history as a child soldier in Solidus Snake's army, which was the reason he was distant from her. Raiden was shocked to learn that she was a Patriot spy and had just become pregnant by his child. Rose was taken hostage by the Patriots shortly after her communication line was cut.
The Patriots made an artificial AI program that mirrored Rose in a last-ditch effort to discourage Raiden from entering Arsenal Gear. Snake then tried to claim that the Sons of Liberty had Rose on Arsenal Gear. However, Snake snatched Raiden out of it. This also led to Raiden becoming disoriented at the possibility that Rose might not have existed. The program eventually interacted alongside Colonel AI with Raiden when they revealed their motives and existence to Raiden at Federal Hall. Raiden was then warned by the Patriots that if Solidus is not eliminated, Rose, their unborn child and Olga Gurlukovich's child would be killed.