J.K. Rowling has said in interviews that Luna married a character named "Rolf Scamander". No character of this name ever appears in the novels. Did Rowling just invent him for the interview?
What happened to luna, did she get married who to?
J.K. Rowling: Luna became a very famous wizarding naturalist who discovered and classified many new species of animals (though, alas, she never did find a Crumple-Horned Snorkack and had, finally, to accept that her father might have made that one up). She ended up marrying (rather later than Harry & co) a fellow naturalist and grandson of the great Newt Scamander (Rolf)!
Bloomsbury Live Chat - July 2007
And what happens to Luna?
J.K. Rowling: Oh, Luna marries um... Rolf Scamander, who is the grandson of a great naturalist, so they'd have a very interesting life, globetrotting and looking for weird animals. But I think she'd have twin boys. But later. That would be much later than this lot who all settled down earlier.
And are they happy?
Um, yes, I think so. My lot are all happy.
The twin boys have got names too?
Lorcan and Lysander. If that's alright with you.
JK Rowling A Year in the Life - December 2007