According to the Bible, after they begged him, Jesus gave permission for the many demons of the man called Legion to leave the man and enter into what?
“Jesus then asked him, “What is your name?” And he said, “Legion,” for many demons had entered him. And they begged him not to command them to depart into the abyss. Now a large herd of pigs was feeding there on the hillside, and they begged him to let them enter these. So he gave them permission. Then the demons came out of the man and entered the pigs, and the herd rushed down the steep bank into the lake and drowned.“Luke 8:30-33 (ESV)