This manga is about a girl and two boys, I think they are twins , I am not sure. The two boys are complete opposites of each other, one boy treats the girl really nice and gentle, while the other boy bullies the girl and treats her mean and calls her name. The girl is in love with the nice boy. There is an accident and the boys switch bodies. Because of this incident the girl starts to fall in love with the other boy who was mean to her. In the end the nice boy confesses to the girl and he tells her because he was in the mean boys body he felt compelled to. The mean boy's feelings influenced the nice boys. The girl end up with the mean boy.
I devoured the five lands I swallowed the three seas But I could not reach the sky In this body with no wings No arms and no legs I am the world serpent I am Jormungand