Jusenkyo
Jusenkyo is the fictional 'cursed' springs from the Ranma ½ manga and anime. Jusenkyo is located in a secret area of China.
Spoiler warning: Plot or ending details follow.
Many bad things have happened in Jusenkyo, mainly that people and animals have drowned in the various pools hundreds or thousands of years ago. Legend has it that when something drowns in one of these pools, the pool becomes cursed, and anyone falling into that pool will become whatever drowned there, although they retain their mind, personality and abilities. The cure (albeit temporary) is to be splashed with hot water. Then you remain in your natural form until again encountering cold water. For some strange reason, Jusenkyo has become a 'proving ground' for martial artists.
On the Ranma 1/2 series, people have accidently fallen into the springs of the drown girl, panda, duck, piglet, and cat, and at least one character chose to voluntarily bathe in one of the springs.
Due to the series' enormous popularity in anime fandom, the springs were often used as a quick plot device by role players wanting to create characters who were essentially functional transsexuals without the emotional or social baggage, Purist fans of the series point out the original Japanese wording does not technically imply the original victims of the spring needed to actually drown; he or she can be involved in a near drowning. One of the characters in the series (Akane Tendo) in fact caused a pool to become cursed without actually dying.
