As per my "tastes" here is twink
Bali (Indonesia), Cambodia, Myanmar, Philippines, Thailand, Vietnam and Laos: gay guides and companions http://siamroads.com
christianpfc (January 17th, 2017), francois (January 16th, 2017), ggobob (January 15th, 2017)
My general understanding of the term is of a boy who is old enough to have sex, but too young to shave, is slim and cute but not overtly fem.
I recall it being said that twinks were by definition natural blondes, and that Thais could therefore not be twinks - but I don't buy into that.
Perhaps a simpler definition would be to say that when you see a slim young guy and your first thought is 'God, I'd love to snog that' - you're looking at a twink..
A twink for me is an Asian under 25 , slim and a bit on the fem side,
A farang twink must be under 20 to be considered twink in my books.