Space Monster DEMEKING
Junior high school student Hiroshi, who will only play with younger children, meets the young, taciturn Hachiya as he rides his bike. Shortly after, a strange friendship begins to blossom between them. But then Hachiya disappears, leaving behind only the puzzling words, "I am going to fight Demeking."
Directors: Kôtarô Terauchi
Writers: Takashi Imashiro
IMDB: tt1386609