I was remembering everything before I was possessed by Xana. How I promised to keep their secret and how I went in the scanner to be immune from Return to the past.
Actually I remembered Everything.
Then I saw Yumi on Lyoko talking to me in a soothing voice telling me to remember what I promised to the Group.

To The Lyoko Warriors.

To her.

I was listening to her. After she finished, I whispered something in her ear before I was possessed by Xana again. After I was possessed by Xana again I tried to slice her but then Aelita came threw an energy field at me and I fell into the Digital Sea remembering what I had whispered to her.

"I will come back someday and when that day comes we'll be together again ok?", I said looking at her.

"Okay, William I'll be waiting for", Yumi said looking at me with sad and pleading eyes.

"Goodbye", I hear myself say.