Somebody had to leave the Great American Bash with two belts (barring a screwjob finish) and it ended up being the looming Keith Lee. By ending Adam Cole's 13-month reign as NXT champion, Lee now totes around two championship belts, including the North American title that he's held for quite some time. And he's far from the first double champion to come under WWE's auspices.
Particularly in recent years, double champions have been a somewhat-regular occurrence in WWE. More often than not, the example in question is a singles champion that wins the Tag Team belts with a makeshift partner, but there have been plenty of singles double champs like Lee. Sometimes said wrestlers tote around both belts for however long, and other times, they lose one fairly quickly as a matter of restoring balance.
For this list, we're only looking at those who've won two singles belts (preferably with one of them being a World title). And we're looking exclusively at WWE here (sorry, Ultimo Dragon - but hey, nobody will ever be awesome enough to equal your glorious 10 simultaneous titles).
5. Seth Rollins
Former Daily Show host Jon Stewart did all he could to prevent US champion John Cena from tying Ric Flair's stated record of 16 World titles. In effect, he allowed WWE champ Seth Rollins to capture his first secondary singles belt with the promotion.
Rollins dropped the US title back to Cena a month later, which was probably for the best. Though the dude enjoys Crossfit and is in great shape, how was he going to swing two belts over his head? That sounds more challenging than it's actually worth.