Demelza was there accompanied by Geoff Hooper. She was dressed up as a mermaid (though the stomach was less sheer on hers). She had seashells charmed to stay within her blonde curls. She would have danced lots with Geoff and thoroughly enjoyed the Weird Sister performance as they are her favorite band. She would have tried to say hi to Donaghan after the concert to see if he remembered their silly journal conversation from months ago. She'd also hang out with Vicky if she were there and probably Ginny too.