Greet the villain - a shirty type with childish footwear (6)
I believe the answer is:
bootee
'footwear' is the definition.
(bootee is a kind of footwear)
I don't understand how the remainder of the clue works.
Can you help me to learn more?
(Other definitions for bootee that I've seen before include "Baby's woollen shoe" , "Baby's footwear" , "A baby's knitted foot covering - sounds like loot" , "Baby's sock-like shoe" , "Soft, woolly baby's shoe" .)