Possibly the worst thing in the world is Immortality. Humanity describes it as a curse and it is true.
A young man who was strikingly similar to a certain reader knew this from firsthand experience being used as a mere toy for the beings that watch...
Secret Attribute: The Eternal Regressor (SSS-grade)
Grants semi-immortality to the user at the cost of being sent to the start of the first scenario. The user retains his memories and skills yet as part of a penalty for dying the user's skills are halved.