Calvin Harris wants to be Taylor Swift's ''tour groupie''.

The 31-year-old DJ is reportedly keen on following his rumoured girlfriend on her 1989 world tour as much as possible so the pair don't have to be apart for too long.

A source said: ''Calvin is bending over backwards for her. He's fitting himself into her life completely and he's even promised to visit her as much as he can when she goes on the tour. They're making jokes about how he's going to be her tour groupie.

''But they will still have a lot of long distance to deal with and that part sucks, she knows that won't be easy. That's the only drama she's got with Calvin though; otherwise it's pretty much perfect.''

The pair are trying to spend as much time together as possible before the 25-year-old singer heads out for the first date in Tokyo, Japan early next month.

The source added to ''Taylor and Calvin have been spending as much time as they can together before she leaves. Things are moving very fast between them.

''There are no head games and no drama, the only drama for them right now is that they're going to have to spend so much time apart.''