Harry Potter’s Matthew Lewis on Girls, Growing Up – And Emma Watson

Matthew Lewis

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Much like his character in the Harry Potter movies, Matthew Lewis had to go through an awkward period before becoming a handsome hero.

“In the early days, Neville [Longbottom] and I were not very dissimilar – I was a short, chubby, shy kid, just like he was,” Lewis, 22, told PEOPLE about his screen alter ego at a Manhattan press junket for Harry Potter and the Dealthy Hallows: Part 2.

“As he evolved and matured, so did I,” adds the actor – although he admits that he’s still got a ways to go with the ladies.

“You know, girls in general are scarier than Voldemort,” Lewis says with a laugh.

One who’s less intimidating? His costar, Emma Watson.

“Emma is like my little sister,” says Lewis. And he’s taking the big brother role quite seriously: “We have to vet all her boyfriends to make sure they’re good enough for her.”