Because I'm a nerd, I'm aware of many varieties of nerd rock—and just so we're clear, I'm using the term in its narrow sense. I don't mean bands that merely take their names from, say, Tolkien's Middle-earth, but rather hard-core superfans who root all their songs in that world and its stories and characters. (It helps if they've got costumes to match.) The Star Trek universe is another popular source of inspiration, as are the various My Little Pony franchises (maybe you've heard about the 2012 Ponystock festival or stumbled across a "dubtrot" track on YouTube). Twi-rock is an expression of devotion to the Twilight saga, and Time Lord rock (often shortened to "trock") pays homage to Doctor Who. In 2013, in fact, the Reader ran a substantial story about a local trock group called Time Crash, perhaps better known as "that band with the TARDIS guitar."
Probably the best-known species is wizard rock (also called "wrock," but for obvious reasons mostly in text), which is all about Harry Potter. Massachusetts group Harry & the Potters are usually credited with founding it in 2002, making it arguably nerd rock's oldest extant subgenre. But somehow it took till this week for me to first hear about a Harry Potter-themed metal band.
Muggle Death Camp, a one-man operation by a fellow who calls himself Jim Wicked, has existed since at least 2007, when it released the Avada Kedavra EP. (That's the name of the killing curse in the Harry Potter novels.) According to its Bandcamp page, the project is based in Harker Heights, a town in central Texas that's north of Austin between Temple and Killeen. And in May 2015, after nearly eight years of silence, it released its debut full-length, Seven Murders: The Fractured Soul.
Muggle Death Camp has adopted the outlook of Harry Potter's chief antagonist, Lord Voldemort, who wanted to purge the wizarding world of all those not born into it—in the books, anyone without magical blood is called a "muggle." The title of Seven Murders: The Fractured Soul refers to the horcruxes Voldemort created in an attempt to achieve immortality; a horcrux is a powerful object created by a dark wizard to conceal a fragment of his soul, and the manufacture of each one requires the taking of a life.
I can't understand most of Wicked's lyrics, but several of the album's songs clearly take their names from Voldemort's horcruxes. "The Black Stone of Gaunt House" refers to the ring that belonged to his grandfather Marvolo Gaunt, while "Salazar's Treasure" refers to the locket made by his distant ancestor Salazar Slytherin. "What Lies Behind the Scar" is of course a reference to Harry Potter, who was unknown to Voldemort the seventh horcrux. When the dark wizard attempted to kill the young Harry, the boy's mother sacrificed her life protecting him, causing Voldemort's curse to rebound and tear loose a fragment of his own soul; it entered Harry's head and left behind a lightning-bolt scar.
I don't know about you, but this record is kind of making me want to read those books.