Enemies to lovers (Douma x reader)

"My, my, what a pretty little birdie~"

So basically, Douma killed your sister when you were really young. Years later, you're in an orchestra and play flute. He washes you practice, goes to your performances, but after every show, he sends you red roses. Anyway, nobody knows his name or who he is, so they refer to him as "the man with the rainbow eyes."
Will you figure out who he is?
read to find out ;)