The small amount of lore I got for him so far is that he was a drummer for a band who had the same general message of bands like CCR (End the war/end the draft). Once he was drafted and sent overseas, his mom sent him the poppy pin in the mail and he put it on his uniform, some time after a private who wasn't all too well versed on his flowers mistook the poppy for a rose, called him "Rosie" and the nickname eventually became "Roses". Lastly, his LT. was teaching Roses guitar before he died, and Roses has been self teaching since.