Fallen angels fell from heaven because they did not listen to God.
When God casts fallen angels out of Heaven, They usallaly land in bad places that are scary and where people can get lost. They can land in the dark woods, cemeteries, abandoned dark places, and in places with no food or water. The grim reaper is a fallen angel. But the most famous fallen angel is the Devil. God kicked the Devil out of Heaven, and he became the king of the underworld.
Fallen angels always land in a pile of jagged rocks or boulders really hard. Sometimes they even land on metal army buildings! It is very tough and scary to be a fallen angel. Imagine, Falling! falling...falling...CRASH!