Valkyrie Choukyou Semen Tank no Ikusa Otome Vol. 1

The main character is the youngest child in his valkyrie family. He was supposed to be born as a girl, but he is a boy. Due to this, the balance of the world begins to collapse. He is considered as the cause of this phenomenon and sent to a world where humans live. He learns how to get a girl's body using magic there and takes back the world balance. When he is about to go back to the valkyrie world, Fenril, the boss of Helheim, tells him, "You were exiled from your country before. Your country is also burnt down...." He gradually holds a grudge against them. Brynhildr, a valkyrie, tries to calm him down, but his hatred never disappears. Who will gain the initiative of this battle...?