Oh

you rarely EVER see hair being drawn, sadly. the only times I see them drawn, it's usually in a manga.

Their testosterone for hair in their body usually goes to their dick ig

my headcanon is:
Shin: Asian genes gave him scarce and thin body hair.
Jay: He lasered it off (???) bc he couldn't risk leaving any kind of visible dna evidence during his cia missions.
Both are kind of a reach but they allow me to stop questioning it and keep reading lol.