“Twunk” is a term combining “twink” and “hunk”.
A now not sexist term used to describe a younger man (usually between 18-25) that has the face of a “Twink”, with the physique of a muscular person.
Usually a “Twunk’s” body is not as “ripped” or muscular as a “hunk”, but if they went to the gym, the “twunk” could accomplish the body of a hunk.
The word “Thunk” is used to describe homosexual men. Usually used when talking about a small looking guy that is the one to receive/”bottom” during sex.
A “hunk” is a retro/older term that people use to describe more attractive man.
It was combined by using the words “Twink” and “Hunk” to create “Twunk“ as a joke at first.
Since these two contradict each other so much, it is weird to hear someone say it. Alex Henley from skins is a prime example. First entries into the Urban Dictionairy happened as early as 2006.
Widely used in news articles, blogs and social media sites like tumblr as the word is not considered sexist.
It is not considered an offensive term anymore, but you will not often hear it in public as its typically used in erotic context.
As these sayings are more and more common in youth slang, the spread of twunk has since reached a global level and there is a wider knowledge of its meaning.