Folktales are often dramatic, fascinating, and full of life lessons you should ignore.
Take this story about Kebara no Myōga, a man whose name was only a tad more impressive than his decision-making skills. He was taking a walk in the mountains when suddenly a beautiful woman appeared and asked for his help. “There’s a shiny bauble at the bottom of this pool, would you get it out for me?” she asked unsuspiciously while batting her eyes using lashes that caused typhoons in their wake.
If folktales teach you one thing, it’s that gorgeous women hanging around bodies of water are either really good news or really bad news. Myōga, apparently the gambling type or quite stupid, dove into the pool with the energy of a puppy overeager to please. He retrieved a little statue of Kannon, the Buddhist goddess of mercy, from the bottom of the pool.
When she received the statue, the woman promptly went through a Sailor Moon transformation and became a princess of the Dragon Palace. “Before I return to my not-further-explained mystical realm, what would you like as a reward for getting wet for me?” she asked.
If folktales teach you a second thing, it’s that you will get in a lot of trouble wishing for things without being very, very precise. Myōga, fully confirming his membership in the stupid camp, immediately asked to have the strength of a thousand men.
She granted his wish. And he regretted it.
Myōga started walking back home, but each step collapsed the mountain beneath him. As he tried to pull himself up, he uprooted trees. Every flex of his mighty muscles tore his clothes. Myōga crawled back to the princess who was rolling her eyes pretty hard at this foolish half-naked mortal by now.
Luckily, she was in a good mood and agreed to change his wish. “I would like to have strength as needed,” said Myōga, careful as a tiptoer in a field of Lego. “If something weighs a hundred kamme, then I want strength to lift a hundred kamme.”
After rolling her eyes once more (this time at his units of measurement, which were only slightly less confusingly useless than the imperial system), she granted his wish. It was a perfect wish, save for one minor condition that would surely never bite him in the ass. He was never to hand anything to a woman, or he’d hand his strength over, too.
And from then on, he fumbled it again. Given his eagerness to please women and the prodigious mental acuity he displayed so far, it is no surprise that Myōga absentmindedly handed his strength to his wife one day together with some groceries she’d asked him to get.
Since that day, his female descendants have all been incredibly strong, while all his male descendants are cursed to struggle with jam jar lids.
Moral of the story? Let your wife do the groceries, I think.
Oh, why did the strength power only transfer to the female descendants? There’s a traditional belief that daughters belonged to mothers and sons belonged to daughters.
I think the celestial bastards in all these stories around the world entrap mortals into "earning" wishes and then grant them in problematic ways, just for their own cruel amusement.