Events of Red Dead Online
Cooper provides provisions, tonics, clothing, weapons, hunting and fishing accessoires and horse gear to the protagonist.
Events of Red Dead Redemption 2
The player can learn that Cooper is running an illicit moonshine still in the basement of his store. The player can then rob their side business.
Cooper appears as friendly, greeting the player when they enter his store and conversing with them from time to time. He is also shown to be helpful, even to strangers, as seen when he temporarily employs John Marston during "The Wheel".
He appears as a middle aged man with brown eyes, swept back black hair and a mustache. Cooper is always seen wearing glasses, a thick black sweater and a white full body apron. Notably, Cooper's right leg is missing from the knee down, and he wears a wooden prosthetic.
In 1907, his appearance seems to have changed little, although he is shown to have a bushier mustache and now usually wears a red sweater instead of a black one.
Red Dead Redemption 2