When Itsuki and Chitose visit Amane's apartment for a Christmas party only to discover that the angel Mahiru lives next door, they instantly become very curious about the relationship. Chitose, obsessed with cuteness, insists on becoming friends with Mahiru. The day after Christmas, Amane notices that Mahiru has a fever. Despite Mahiru's stubbornness, Amane convinces her to stay and rest in his room. When Mahiru sees Amane so diligently taking care of her as if returning the favor she did for him that one memorable day, it seems to put her at ease.
But I know that's my fault, 
so I really should apologize.
لكن أعرف بأنّها غلطتي، لذا ينبغي أن أعتذر
Y sé que es culpa mía,
así que debería disculparme.
Y sé que es culpa mía,
así que debería disculparme.
Enfin, j’y suis pour quelque chose…
Je suis désolé.
Però, so che lo fai anche per il mio bene,
mi spiace importi un tale peso.
Mas, eu sei que é minha culpa,
então me sinto mal por isso.
И мне очень жаль, 
что я тоже в этом виноват.