Show a Scar.
Ill go first...

Too young for Jr guys, not a single gray hair there. Doesn't appear to do manual labor for a living but his palm focus is a bit off so not %100 on that, wears sleeves occasionally (like recently with the weather cooling but not normally) as there are only some noticeable broken-off follicles about the wrist but not as you'd expect from someone wearing a jacket sleeve all the time. Hairs appear broken off at the wrist side above the thumb heel and not top like from the writing hand positioning, not a mouse/keyboard as the right/mouse hand would be positioned to break more hair off across the top/back with hand rotated accordingly. The scar at the side combined with the scars at the hand heel to me would seem to record a lot of childhood falls reflecting a rowdy or active youth in sports/play.
The desktop color/type looks like some institutional furniture as you'd see in a lab or school, maybe a college student/young teacher?
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Just my 2cents of observations.