Would appear to be a house plant.

Here is a link that might be useful: Desert Tropicals - Euphorbia sekukuniensis

My plants look nothing like that. Now I wonder if they were mislabeled. Not out of the question. My husband picked them out at a plant sale because he liked how they looked. No real info other than the hand-made tags. Here are some photos. Any thoughts?

It looks more like the E. griffithii type. Maybe 'Fireglow'

It is deciduous/ herbaceous, and will run a bit underground.
Best color will be in sun.

Thanks plantknitter! That looks a lot more like it.

I think your pictures are of Euphorbia griffithii Fireglow cv.

Correctly fashioned 'Fireglow' and not Fireglow cv.