8. Castiel (Supernatural)
Castiel, played by Misha Collins, was a late arrival to the series, not showing up until near the end of the fourth season for a six episode story arc. But when that arc, and with it Season 4, both came to a close, the fans were on the internet in full force demanding the fractured angel's return. The character became so popular and beloved in fact, that the series, which was built entirely around two brothers traveling America fighting demons and monsters, became a trio, with Castiel becoming a series lead right beside Sam and Dean. I myself have only seen barely a handful of episodes of Supernatural. (It's on my To-Do list I swear!), but my fangirl friends explain to me that Castiel got over so huge with fans because Misha found the perfect blend of "I was an Angel and you people are beneath me" and "I'm so broken and afraid please help me understand this world" that an angel in not-so-good standing should have. He shows a restrained subtle vulnerability that speaks to the fans, and it cemented him as a major player in the series, now about to start its 9th season on the CW.