When one eye is covered - usually by hair or by part of a hat, it evokes the playfulness of a child's peek a boo game. As we grow out of childhood, in the context of romantic relationships, this playfulness overlaps with and morphs into a sex appeal. While it is certainly more common with women and those who are androgynous, it's also a body language signal seen in straight men with longer hair or with the brim of a hat.
When flirting, one should take care not to stare with the uncovered eye. Only short glances, with brief eye contact - made only for a second or two - then broken by looking down (not sideways) - and then reestablished for another evanescent moment - will send signals of sexual interest. A simultaneous sincere smile (Duchenne smile) - particularly a partially suppressed one, will potentiate the message of sexual attraction.
Displaying only part of the face also adds to an ambiance of mystery - which helps with advertising, attention and establishing romance.
Thank you Prince - you'll be missed. My condolences to your friends and family.
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