I went to Petland today and swung by their betta section. They had just gotten in a new shipment, the fish all looked wonderful and the water was crystal clear.
And then I noticed two bettas in one cup. One had jumped right into the other's cup and they had totally ripped each other apart. After freaking out a little, I found the empty cup, washed my hands and transferred one to it. Bits of fin were everywhere, one of them was in really rough shape.
And then something caught my eye, a little flash of blue.
There was a betta in the sink. He had jumped out of his cup and into the basin (filled with murky, untreated, standing water) and was swimming around in there under a bubblenest. I found his cup and quickly scooped him back in there.
AND THEN. I saw, next to that cup, YET ANOTHER empty cup. I found its former occupant dried to a crisp on the side of the sink.
There were still two empty cups whose fish were missing when I had to leave.