An erotic desire to return in thought, or in fact, to a previous sexual/romantic experience. This takes place many times during masturbation or just simply during day dreaming. Rapists practice this form of reminiscence about their former lovers/victims. This is best succeeded when a rapist uses rapies, a sort of memento, to remind him of the encounter. Romantic nostalgia is also practiced by priests when trying to remember a certain sexual molestation victim that they liked but is no longer around to love/sodomize because they told their parents about the molestation.
"If it wasn't for romantic nostalgia, I couldn't have sex with my ugly, fat girlfriend."
"The devout priest kneeled before the cross and thanked God for romantic nostalgia and for supplying him with many children to sodomize."