From the introduction:
Yo! Welcome to Earth! Well... Not necessarily the Earth you know. Different towns, different cities, that sorta difference you know? But the real difference, what separates this Earth from your home and other variants, is the existance of many, very extraordinary people. Well okay, every world has extraordinary people, but these ones are particularly bizarre. And due to the... Whoever it was that sent you here, you’ve become one of these same people.