I often have dreams that are unsettling, disturbing or just plain weird. I also have anxiety or process dreams that seem to recur all night. Monsters are not the things that keep me awake. My insomnia does that.
But this one scary dream was really vivid. I was riding in the back seat of a car. It might have been a cab with a partition, but suddenly the partition was gone. In the driver's seat and facing me was a giant crab. Not the monster.
As it snapped its claws at me, lights came on inside the claws revealing the monster. In each claw was an creature that looked Alien. Snake-like with long sharp teeth. The twin creatures move towards. Snapping. Snarling. Dripping who knows what on the floor between us.
Just before I woke up I realized that these creatures also live in the arms of domestic pets.