My world is basically the same as our own but with slightly more advanced cybernetics and virtual technology. Specifically, they have a technology to create true matrix level virtual worlds. The most popular of which is based on a fantasy RPG. Users connect their minds to the virtual reality and choose different classes for their avatars in this virtual world. As they play, they can unlock new skills, abilities, and ability levels. However, as amazing as this game is, it comes with side effects.
Since the game is so real you can suffer from post-traumatic stress disorder (PTSD) from your gaming experience. You also feel the pain as if it were real. And most frightening of all is that the more you play, the higher is a risk of a coma or even a complete brain death, should your avatar experience death in the game. The chances of death in the game resulting in actual death increase with the time spent playing the game.
Yet despite this, over 1/3 of the world population spends one day a week playing the game. 1/5 of the population spends 3 days a week playing.
Assuming that these gamers are relatively sane why would they keep playing even knowing the risks?