Thanks to Gordon’s father, Asta and the others were able to find out that there might be clues surrounding the devils in the Heart Kingdom and manage to get permission to enter the kingdom due to the fact that Mimosa had gone there previously to study overbroad. Asta, Noelle, Finral, Mimosa and Nero head to the Heart Kingdom. Asta and the others initially enjoy their trip there, but something that Langris told Finral had been bugging Finral. Suddenly, Asta and the others are faced with a rather unexpected trial. Will Asta and the other Black Bulls be able to obtain information on the devils?!
Could it be that the Heart Kingdom 
has been taken over by a devil?
هل يمكن أن يكون شيطان 
ما قد استولى على مملكة هارت؟
Sollte Heart etwa bereits
von einem Teufel beherrscht sein?!
¿Acaso el Reino del Corazón
está bajo el control de un diablo?
¿Un diablo controla
el Reino del Corazón?
Se pourrait-il que ce royaume
soit sous l’emprise d’un démon ?
Che il regno stesso sia stato conquistato da un demone?
Será possível que o Reino Heart
está tomado por um demônio?
Неужели королевством
 уже завладел таинственный дьявол?!