This is type of black snake that is common in Korea.
The story goes that before the start of the Korean War my great-grandmother encountered a black, snake in her kitchen slithering around and eventually leaving the household.
With an American point-of-view this would have been a sign of relief but in Korean culture it was the surest sign of financial ruin. Sure enough my great-grandfather passed away and his assets were seized by his father and his sons from his first marriage.
My grandmother was only 6-years-old at the time when he had passed away from stomach cancer. With whatever money my great-grandmother had been able to earn she invested nearly everything on a mine hoping to earn a fortune but alas it was a financial failure. My great-grandmother worked hard but still died in poverty and for 30 years my grandmother too had struggled to earn a living and raise her family.
My grandmother had never questioned the bad omen and knows not to dismiss old Korean superstitions. I too take her words to heart and know not to dismiss such superstitions immediately.