Possessed

... The novel is the biography of a talented female musician who falls in love with a composer of organ music of extraordinary abilities. In the course of their romance she realizes that he is deriving his abilities through supernatural evil means, which keeps the Church from allowing him to take a position as an organist in spite of his nearly otherworldly compositions and performances. A special emissary of the Church is sent to help him overcome his demonic connections. During a grand tour through Europe things escalate and come to a dramatic and tragic end when the female protagonist realizes that she is pregnant and takes steps to protect her unborn baby.