Mystery plant

The association rules say we are allowed to plant things within three (or maybe it's four) feet of our foundation. There isn't much in that area that isn't already covered by various types of bushes, but that didn't stop the previous owners.

I popped out to take in the mail yesterday - when it was both still daylight and not raining - and discovered this blooming betwixt the bushes:

I was barefoot, not wanting to walk outside that way, and only managed a rather sideways view that doesn't do the blooms justice. They are truly a gorgeous medium purple, five petals, with bushy foliage. Obviously, they are some sort of perennial.

Some variety of clematis? As pretty as it is, that could be a problem. The stems and flowers have an essential oil that is extremely irritating to both skin and mucous membranes. This beautiful bush appears to be planted either directly in front of or right next to the outdoor faucet. I'm going to need to wear a beekeeper's outfit every time I want to use the hose.

Based on my very quick look and the picture, this may be a Fuji Musume or a Ramona variety, or one of several other similar blooms. No matter - the pruning instructions are the same for all, so even I can't completely mess it up.