When Twilight tries a mass teleportation spell with her friends they get stuck in another universe. What's worse is that their landing point was a magical spring that curses it's victims to transform into whatever drowned there. They are now cursed to turn into human girls whenever splashed with cold water, but hot water changes them back.
They weren't the only ones to fall in that day. They meet Ranma a male traveling martial artist who fell into the same spring (meaning he turns in a girl), his father Genma who becomes a Panda. Twilight agrees to cure them when she figures out a cure while they give her and her friends a place to stay.
Due to a series of events, they wind up in Japan where they must pose as normal high school girls. Where they must deal with a stupid swordsman who falls in love with them, martial arts based on running, rhythmic gymnastics and figure skating, rivals from those sports. And that's barely scratching the surface of the insanity that lies for them...
Edited by NightElf37 (chapters 1-16), Alticron (chapters 17 onwards) and Dr. Tempo. Cover art by by Schreibaby-Zephyrof deviantart