When to Delete Monika?

Delete Monika's file directly before reopening the game. Worth noting that the delete buttons for each system are the X button on the Nintendo Switch, the Triangle button on Playstation, and the Y button on Xbox. Players will know it worked when they start the game up again and see that Monika is no longer there.

What happens if you delete Monika early?

If the player decides to delete Monika from the game, Monika will then glitch out, before becoming disembodied and angrily expressing her disgust at the player. She will then claim that she made a mistake and express her regret at what she has done to her friends.

When should I remove Monika for good ending?

Delete her character file after you've written a poem for her and she has begun to stare at you. You are now on the track for the secret ending. Play through as you normally would, re-running the game until you are back at the start with Sayori as president.