Placeboi
A male fan obsessed with the English rock band Placebo. Especially Brian molko.
Placeboi's usually dress in black and wear eyeliner. They unabashedly wait hours to be front row at placebo concerts.
Placeboy
A boy or man that essentially behaves as a boyfriend but does not receive the title or physical benefits of the position. Typically seen as a friend by the other person rather than a romantic interest. This person provides the emotional support and care that is associated with a good boyfriend but is essentially a placeholder for the other persons lack of romantic partner.
She didn't want to date me so I was basically a placeboy to her until she got her current boyfriend