What would be a metaphor for a "Twisted past"?

A figure of speech is a departure from the normal patterns of language for the purpose of emphasizing something. The simplest figure of speech is the SIMILE. A simile emphasizes a similarity of two things by merely saying it: "You are like a dog", or "You are as a dog". The figure rests entirely on one word.

A METAPHOR emphasizes a similarity of two things by saying they are the same; "You are a dog".

Next comes a big word: HYPOCATASTASIS. This is a Greek word for name-calling. Hypocatastasis just calls the fellow "Dog!" See Luke 13:32 "that fox", and Genesis 3:1 "the serpent".

A PARABLE is an extended figure of speech; a story based on a simile, metaphor, or hypocatastasis. If the story is possible, it is a MYTH. If the story is impossible, it is a FABLE. If a fable includes an explanation of the meaning, it is an ALLEGORY. Don't confuse any of these with LEGEND, which is a supposedly true but unverified historical account (Adam and Eve, for example).

These terms are not used with any precise meaning in modern discourse. For instance, most people think 'allegory' means "a story full of religious symbolism beyond human comprehension". But when discussing figures of speech they are very precisely defined. Here is a book that lists about 900 figures found in the bible. It is almost the only work in the subject for the last two thousand years:
openlibrary.org/search?q=e.+w.+bullinger+figures+of+speech

More figures: mentalfloss.com/article/60234/21-rhetorical-devices-explained

Ok, so you want a figure of speech to ... Wait a minute, what exactly do you want here? I suspect you want something that will show the world what a clever writer you are. Well, I want you to know that trying to be clever will only get you into a collection of dumb things youngsters have written while trying to be clever. That's where you see stuff like "It skated across the lake exactly the way a bowling ball wouldn't," or "He was as tall as a six foot three inch tree." My advice is don't do that. Just figure out how you want to describe this guy's past and write that. It will be much better than any wonder of wit that you get from somebody else.

Besides, I guarantee your teacher will be blown away when he realizes that you understand a half dozen figures of speech. When I was in college English my teacher was blown away when I mentioned just one figure, synechdoche. Except I pronounced it "sin-ek-dosh". He told me it's pronounced "sin-ek-do-key".