Ian Somerhalder and Nina Dobrev of The Vampire Diaries

Character names: Elena Gilbert & Damon Salvatore
Years dated in real life: 2

Though she's 10 years his junior, photos show the 23-year-old Nina Dobrev is getting serious with her co-star Ian Somerhalder. The two met on set, while Ian was playing a bloodsucking vampire who regularly tows the line between protagonist and antagonist. While the show's a hit and their individual star power continues to grow, the couple has somehow maintained a relatively low profile in the press.