Blame adzuki beans
I have no clue how the last translator got "puberty" out of 小豆. They only have a few translations so I think this is either trolling or inexperience. I'm leaning toward trolling because it's so far from any puberty-related words. The only thing I could think of that makes it make any sense at all is just guessing 小(small) + 豆(bean) = clitoris = puberty (somehow?)