In Level E, Tokyo-born schoolboy Yukitaka Tsutsui moves to Yamagata Prefecture for high school on a baseball scholarship. Because he attended the top middle school in Japan for baseball, the townsfolk eagerly await his arrival. Instead of a quiet start, Yukitaka finds a strange man in his apartment, casually reading and even wearing his clothes. The intruder claims to be an alien who crash-landed on Earth and has nowhere to go, then reveals himself as Baka Ki El Dogra, the crown prince of the planet Dogra. He is only one of the hundreds of aliens that have already made Earth their home, unknown to most humans.
Despite his regal origins, the prince is an infamous intergalactic fool who thinks nothing of inconveniencing others for his own amusement. He runs ridiculous tests on his subordinates, gives strange powers to random children, and turns everyday life into a series of escalating pranks and disasters. As Yukitaka and everyone around him get pulled into his schemes, nobody is safe from the idiot prince's antics.
