When someone falls deeply in love with a fictional character they have projected onto a real person. A type of infatuation often specific to people with high standards and romantic ideals.
Person 1: OMG Justin Bieber is perfect! I'm in love with him!
Person 2: No hun, you have an apollonian crush on Justin Bieber. Since all the boys at this middle school are below your standards, you have projected your idea of an ideal romantic partner onto a person you will hopefully never meet.