I have seen at least 1 meme or other joke somewhere on the platform where one also mentioned a "twink" and where that word appeared to be the punchline somehow. I've scrolled through Urban Dictionary a bit (haha) and the meanings mentioned there are either literal, using burger as a metaphor for the kind of person who looks like they consume burgers regularly, as a random surrogate for things that are kind of round (haha) or even that aren't, or 1 Instance of fandom ship name for piece of media where the name of a character sounds like the word for onions in Japanese. That didn't really get me anywhere. Did I correctly pick up that I don't get it, or is there nothing more to this word?
Bears and otters both share being fairly hairy to some degree. Bears is usually applied to bigger men, and also typically to masculine presenting men as well as being past the mid twenties in age.
Otters may or may not be bigger, but are typically much more feminine presenting. You will sometimes see it applied more to small, hairy men, but that goes back to slang being variable by default.
Now, to complicate matters, there are also cubs. Cubs are just young bears. This means that they may well be smaller and less hairy than most bears, and will get lumped in with otters despite otters being feminine presenting as the standard usage of the term.