You know what? it's fine. sorry for bringing this up.
The videos are really just the empty dialogue boxes. They just happen randomly out of nowhere every single time at different parts of quests/ after quests are completed/between generic dialogue. I don't know what causes them to appear. (for me at least)
Most of the times after I reload a map they don't appear where they did. Before I replayed the game from scratch, some did not appear where they did the second time I played.
I have seen it happen with:
Junsa in college. (twice, before and after save deletion)
Reita and Junsa in the hallway in ravaging beast world. (once)
Masuo's mom in Mei's house. (multiple times, before and after save deletion)
Aoi at the table in Sakurai house. (once)
Dahlia in the truck. (twice)
one of the guys in past college. (once)
Ruru in the locker room. (once, before I deleted my save)
They seem random every time they occour.
Also:
1. In the asylum, Momoe hallway toilet is called "nurse 1".
2. Dahlia has wrong costume sprite after I give her salt costume.
3. Hitomi has weird multiplying character words when I am able to ask her to be my assistant. (pressing any button fixes it)
4. When Tatsuka is my site assistant the character picture next to her stamina bar does not change. (it shows Momoko)
5. The long hallway of the void is called "boy's toilet 1. floor" after exiting cell 2 and cell 3.
Edit: sorry for the blocks of texts.