It's hard to pinpoint "One Thing" Louis Tomlinson loves about model Eleanor Calder, his girlfriend of seven months. "I'm a one-woman man with Eleanor,"  Tomlinson, 20, says in Us Weekly's One Direction special issue (out now). "I'm a very loyal boyfriend."

The English pop star and his Hollister model girlfriend were spotted strolling hand-in-hand through the streets of Toronto May 30. "I love him as a person," Calder has said, "not as a member of the band."

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Though One Direction is taking the world by storm, Tomlinson still prefers low-key dates to extravagant outings. "I'm a bit old-fashioned, and I like the idea of going to the cinema and then an Italian restaurant," he admits.

So what does Tomlinson look for in a significant other? "If they're tidy, that would be good -- because I'm not!"

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Tomlinson met Calder, a sophomore at the University of Manchester, through bestie and bandmate Harry Styles, 18. Since then, it's been nothing but bliss for Tomlinson. "I'm a bit of a joker," he tells Us. "I can be a romantic -- but not too sickly."

For more on Tomlinson and his European bandmates, pick up Us Weekly's One Direction special issue, available now!

This article originally appeared on One Direction's Louis Tomlinson Holds Hands With Girlfriend Eleanor Calder