Non-existent Mugen

This person cannot be mentioned, any reference to the name of this person is immediately deleted from anyone's mind. The only theory of it's "existence", are items that have been moved from their places "alone"; you forgetting about what you were going to do when you enter a room (which is theorized you made eye contact with this person); and anomalies in the infrared frequency.

Appearance
Unknown, but it should be similar to the others.

Biography
Unknown, the only thing that can be noticed is that this person has developed some sort of anti-memetic ability, making him extremely dangerous, yet it's unknown how he behaves.