Hilarious, light-hearted and fittingly goofy. I’ve always liked ABBA, and “Mamma Mia” was okay, but the parts I enjoyed the most in your story were the ones close to the HP Universe. For example, the girls’ carefree cluelessness about the war and its heroes and villains was refreshing and fun:
"Mmm, Harry," Lisa sighed. "Sexy name. Hey, haven't I heard that name before? Wasn't Harry Potter a war hero or something?" Ali shrugged. "It's probably not the same guy; that's a common name, after all.
Lucius kept bringing up a group he and Severus had been in—the Death Eaters or some such thing, and since it sounded like a heavy metal band, Eileen teased them mercilessly about it.
Like Eileen, I felt unable to resist your Lucius. He was ever so charming even - or should I say especially - when enthusing about the ”good old days”: "Snap out of it, Severus! Remember the height of your power, when you were the Dark Lord's right-hand man!" Albus cleared his throat and Lucius flushed as he mumbled something apologetic.