Messalina is the name of a Roman Empress, first wife of Emperor Claudius. She was infamous for her promiscuity: apparently, she wanted to have sex so badly that organized an all-night competition and won with 25 partners in 24 hours (this is probably a work of fiction, but she did have lovers, and she secretly married one of them, thus she was killed by the Emperor). "Messalina" is therefore used as a synonymus of "whore". May I suggest another middle name for Luna? Maybe Mary (or Maria)?
Messalina is also the name of the Catholic Saint- a consecrated virgin martyr who refused to submit to the pagan gods of Rome even upon the threat of death. A personal favorite of mine, if you will.