A mangaka is a person who creates manga, which are comic books or graphic novels from Japan. It's like making a movie, but with drawings instead of actors.
Imagine you are drawing a story, and it has pictures with different characters and backgrounds. Your drawings have to tell a story without any words, and someone who reads it will understand what's happening. That's what a mangaka does, they tell stories through their drawings.
They spend a lot of time drawing and using their imagination to create amazing characters and events. Just like how you use your imagination to create stories when you play with your toys.
People enjoy reading manga because it’s a unique way of telling a story, and there is an entire culture that loves it. That's why mangaka are so important, because they’re the ones who create new exciting stories for people to read and enjoy.