The 4th Grader Demon LordMaou wa Shougaku 4-nensei: Tenshoushite mo Sekai Seifuku Dekiru ka na; 魔王は小学4年生～転生しても世界征服できるかな～; The 4th Grader Demon Lord

Shining black armor... A fluttering cape... and... a creaky school bag on his back!? The rumored beautiful female transfer student is a Demon King from another world!