BMSB stands for Bad Motherfucking Stink Bug
I kill several of these every day throughout September and October inside our house (in Central Ohio). Annoyingly, the cats will chase them but never actually kill them (just like ladybugs).
@cwhartman I killed 12 when I took out our window AC unit a few weeks ago. I thought it was a fluke, I didn't realize that they were invasive jerks.