Make Your Own Asuramaru from Seraph of the End Costume

Asuramaru (voiced in Japanese by Hibiku Yamamura and in English by Colleen Clinkenbeard) is a major character in the anime/manga Owari no Seraph/Seraph of the End. He is the demon that is contracted to the main character, Yuichiro, acting as his sword. Not much is known about his past in the anim