The character Spike (also known as William the Bloody, from his fondness for railway-spike based torture), from Buffy The Vampire Slayer, also referred to as 'Hostile 17', is based on Sid Vicious, ex-bassist of The Sex Pistols.
The whole appearance, the unnecessary Britishness, and the fact that he sings the version of My Way from the film Sid and Nancy when he first arrives in Sunnydale all point to this.
He was formerly romantically involved with Drusilla, his sire, and since she has left him for a chaos demon, he has not had any other involvements (apart from a one night stand with the ex-vengeance demon Anya).
Having been captured by the Initiative, he was cajoled by Adam to join him in his quest to rid the world of humanity. However, he refused, and has cemented his place in the Scooby Gang.
Spike is played by James Marsters, and is 127 years old. James Marsters, of course, is not.