If someone is lustful, they have strong feelings of wanting something very much, especially something that is not right to want.
Lustful is usually a bad thing. It can make people think of doing things that are not good or kind.
Examples:
He looked at the cake with a lustful eye.
She felt a lustful desire for the shiny new car.
The man's lustful thoughts made him do bad things.
The cat looked at the fish with a lustful eye.
The dragon had a lustful desire for shiny things.
The pirate had a lustful eye for treasure.