I remember pulling this up on Amazon as a Kindle book a few years back (probably about 2013-2014) where it was being shown as a recommendation due to the books I was reading (possibly Soon I Will Be Invincible: A Novel). The cover showed the supervillain, I think in a purple outfit, brandishing a huge gun in each hand. The bit of the story that I read (a preview) had him doing an interview and explaining his ability to pull guns out of nowhere. I'm pretty sure that his name was themed off of that ability, but I don't recall it exactly.
Anyhow, any chance that someone else recognizes this book?