That happens only when you up/down near door right? Will solved it and update the demo along with v0.1.
I am have recently faced an issue in game. So what happened was that I was speedrunning the game using the cheat codes to complete faith's quest. I captured Thundergirl in Left Hallway 2nd floor. I immediately went to the third floor's girl washroom to test the Old Legend, but after trying I returned to the second floor to see Thundergirl fly towards me and vanish as soon as I pressed the E button. This has happened with me for the first time