From the story of the Greek hero Narcissus who, in most versions of the story, fell in love with the reflection of himself in the water of a pond. He was later then turned into a flower by the gods.
Now the words Narcissism and to be a Narcissit are used to discribe one who is in love with their self or just really really likes mirrors...
Will you please stop looking in that damn mirror you Narcissus.
n. - a male who looks at himself often; a pretty boy
That kid spends more time in the mirror than most girls do. what a fucking narcissus.