How to unlock deleted "Super Secret (Bad)" ending
During the True Ending, after you're told to go to campus 2 to pay your tuition fees (in the room before the one in which you see Security's portrait):

Talk to all 4 people in the room
Interact with all 6 potted plants in the room 10 times each
Continue to the final room as normal
The cutscene is after all the credits.