Capsicum annuum, specifically ornamentals, houseplant advice?

[Fishkeeper]

I'm finding myself fascinated by the number of cultivars that one species of pepper has been grown into. Capsicum annum is the Latin name for the plant that's been bred into bell, cayenne, paprika (which I didn't know was made of peppers) and all sorts of other peppers, and some of those are ornamental.
I tried to grow some Black Pearl peppers from seed, and none of them sprouted after awhile, so I reused the soil in the pot for planting a cactus. Lo and behold, a seedling appears! I've transplanted it into another pot, and it's doing well, but is only just starting to grow leaves other than its seed leaves.
I also just got a 6" tall Hot Pop plant, which grows tiny, round, pea-sized peppers in a range of warm colors. It's adorable.
Does anyone have any favorite decorative peppers of the same size? I'm looking for something that won't ever get very large, houseplant-suitable. I have a South-facing window that's shaded a bit by an outside tree, and it keeps a decent number of succulent species happy, so it should work for these guys. They don't need to be tasty, I won't be cooking with these. I'd prefer to grow from seed.
I've seen pictures of a variety with deep purple leaves, nearly black, and pointed, deep red peppers. Any clue what that is?

 

[Notaneggspurt]

The black leaves with red peppers does sound like the black pearl once the peppers are fully mature. I was trying to hunt up one I had bought years ago that was labeled "Halloween peppers". I'm guessing named so because the peppers were orange and purple. I just got lost in the search rabbit hole! I'll be if no help at this now

 

[Fishkeeper]

Definitely not black pearl peppers. I found a picture- it's called a royal black pepper. It looks about the same as a black pearl, but the peppers are cone-shaped.
There's also a black-leaved beauty called midnight fire, which has slightly streaked peppers that start yellow and ripen into purplish red.
So many pretty plants to grow!