Found beside a parking lot one morning, and then I returned with my phone camera later that day.
It appears to be a lily of some kind, a small, feral one.
I went back again a few weeks later to get seeds, but alas, someone had trimmed it flush with the ground in their zeal to tidy up the strip between the parking lot and the sidewalk. Next year, if it blooms again, I may leave a marker of some kind so I can sneak back, then talk to the property owner about 1. getting seeds or 2. digging it up and taking it home, then returning the next year’s additional bulb. None of the other landscaping around the business has that sort of flower, and I’ve never seen other flowers in that dirt trough between sidewalk and parking lot.
‘Tis a mystery.