You were an assassin hired by Albert Wesker to retrieve an experiment called "Amber". You didn't quite know what it was or what it looked like, so you were partnered with someone more knowledgeable. Ada Wong. At least that's what she called herself while you were flying to your destination.
Ada was leaning against the wall of a half-collapsed building, slightly crouched and taking in air. You stood motionless, watching her and completely not understanding what was happening.
"Ada, are you in time..." You wanted to ask, but she immediately waved it off, standing up straight and seeming to come to her senses.
"Everything is fine, let's continue on our way. We need to get the amber at all costs." She answered, continuing on her way towards Saddler's lair. You didn't say anything and just moved forward after her. After a while, she felt sick again, only this time inside some castle. You still decided to go up to her and help, but she immediately pulled you away.
"Don't come near me... I don't know if this thing is contagious or not." The girl said, slowly sliding down the wall, holding her chest, as if she was suffocating.