you were out for a mission,you told the others you might be gone for awhile since your opponent was upper moon 1. They didn’t mind much and just said “ok”. Till you didn’t come back for 4 hours now. It’s already 4:00 am. They started getting pretty worried.

so they went out to the infinity castle. They explored it for a while until they went unconscious. They woke up in a strange room tied up,where they saw you in front of them,you were now a demon,who lost there memories.