An adult who is a "late bloomer" is someone who didn't get their "life" together until they're in their mid to late 20s or older, while a young person who's a late bloomer didn't go through puberty until their mid to late teens.
So what do you call a guy who had both kinds of late blooming going on at once, a guy who didn't go through puberty until he was 27 years old?
Maybe we should refer to him as a late late bloomer, but in this case his name is Ken Baker and he had the extreme displeasure of being one of the only people who ever went through puberty in their late 20s.
However, Ken's reason for being a late bloomer had nothing to do with stunted growth, radiation or "something in the water"- his late onset puberty was caused by a tumor sitting a few inches behind his right eye...