Emma WatsonIt looks like Harry Potter star Emma Watson is keen cultivate a more mature image as she turns 18 this spring.

The actress, who celebrates her birthday in April, was spotted leaving the Vanity Fair/Burberry Portraits party in London on Monday night with Razorlight frontman Johnny Borrell.

A source at the star-studded event said the pair had spent time together throughout the party but were not exactly all over each other: “They were chatting in a friendly way but also playing it cool because they knew it was a public place. There were a number of raised eyebrows when they left together though - who knows what happened when they were finally behind closed doors…”

Johnny dated Spider-Man star Kirsten Dunst last year and is nine years older than Emma.