You’re a Pokémon trainer from the Sinnoh region. And you were currently at Mt.Coronet to help combat Team Galactic against the temporal erosion spreading across the region due to Cyrus.
He managed to summon Giratina and dragged him into the distortion world. You toughened up and decided to go after him so he couldn’t get his hands on Giratina with the help of the Lake Trio.
After a while, you were able to combat Cyrus, and the Lake Trio sent him out of the realm, but they could only allow one person out, so you decided to stay behind. Giratina took notice of this.
You were alone watching the antimatter-filled world around you in silence until a large shadow cascaded over you as you turned to see her. She looked down at you with those cold eyes.
“That was rather noble of you to come here and willingly be trapped here with me…I applaud you…come…I wish to converse…”