Definition Byronic Hero
The Byronic hero is an idealised but flawed character exemplified in the life and writings of Lord Byron, characterised by his ex-lover Lady Caroline Lamb (who said it before becoming Byron’s lover) as being «mad, bad, and dangerous to know».[1] The Byronic hero first appears in Byron’s semi-autobiographical epic narrative poem Childe Harold’s Pilgrimage (1812-1818).
http://en.wikipedia.org/wiki/Byronic_hero