Erotomania is a rare disorder in which a person holds a delusional belief that another person, usually of a higher social status, is in love with him or her.
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The core of the syndrome is that the affected person has a delusional belief that another person, usually of higher social status, is secretly in love with them. The sufferer may also believe that the subject of their delusion secretly communicates their love by subtle methods such as body posture, arrangement of household objects and other seemingly innocuous acts (or, if the person is a public figure, through clues in the media). The object of the delusion usually has little or no contact with the delusional person, who often believes that the object initiated the fictional relationship. Erotomanic delusions are typically found as the primary symptom of delusional disorder, or in the context of schizophrenia.
Occasionally the subject of the delusion may not actually exist, although more commonly, the subjects are media figures such as popular singers, actors and politicians. Erotomania has been cited as one cause for stalking or harassment campaigns.