Rinoa is a target in the Adel boss fight in Final Fantasy VIII, fought at the start of disc 4. In this battle, Rinoa is junctioned to Adel. If she is killed, it is Game Over.
The start of disc 4 is the point of no return, as after Rinoa is taken to Adel, the party refuses to exit the Lunatic Pandora without saving her.
Adel will frequently drain HP from Rinoa. If Gilgamesh is summoned, he may inadvertently kill Rinoa with Masamune or Excaliber, as his attacks strike all targets.
The player can mug eight Megalixirs from Rinoa, but must be careful not to kill her in the process.