The distinction is slight but still significant= TWINKS are young and slim, almost waif-ish, while YOUNGBLOOD refers to the more toned, muscular but still young guys, almost but not quite as built as hunks or jocks.
A good example of twinks would be- Julien Breeze, or Staxus performers- Ray Mannix and Jacob Waterhouse.
Youngblood would be young like a Twink, but have bigger, firmer builds like Kinky Angel Jack Harrer or Gino Mosca.
julien breeze.jpg
staxus-ray-mannix-and-jacob-waterhouse.jpg
breakfast jack harrer.jpg
Gino Mosca.jpg