Not a trap, really. He was training in China with his dad when the fell into cursed pools. His dad fell into the pool of the cursed panda where hundreds of years earlier, a giant panda fell into the pool. Now every time his dad get splashed with cold water, he turns into a giant panda. Ranma fell into the pool of the cursed girl where a young lady ("girls" built like that??? Woman) had drowned hundreds of years ago. Other characters that have taken a plunge, rival Ryoga, pool of drowned pig. Shampu, pool of drowned cat. Mousse, pool of drowned duck.
While there are tender moments in it, it's pretty much a screwball, romantic comedy. Before I let my granddaughters watch it, I had to discuss it with their mom because it stops just short of full frontal nudity. Yes, it shows na-nas. So far, I've got four seasons of it. One grand daughter has seen season one and two, another has seen seasons one thru three, and the other two, none. (Well, one doesn't live close enough to come visit)
Ranma has several fiances. All at the same time. All arranged marriages by his father. Except one. He got her in a battle without knowing the rules. But then, she was trying to kill the girl version.