He is studious and quiet but hardworking and devoted. Not only is he mature, he is also quite protective of his friends. He devotes himself to studying and can be quite brave, evident from challenging a Behemoth alone. He is troubled by his short stature and feminine appearance that led to people hugging him. He is usually composed and quiet but displays excitement whenever Silhouette Knights are mentioned. He can also be quite forceful evident when he skip and exempt himself from other classes to attend classes about Silhouette Knights. His goal is to create a Silhouette Knight and become a pilot.
Eru's original incarnation in Japan. Kurata was an otaku obsessed with robots, which helps explain Eru's own interest in Silhouette Knights. He is killed in a car crash and reincarnated as Ernesti in the new world, starting the story in the first place.
He later becomes the driving force and the Head Knight behind a new order of knights called 'Silver Phoenix Knights' and gained direct access to the National Technological Robotics Laboratory.