Summary from readers POV:

In 'Fallen' Taehyung is upset with God. He misses Eun Ji and forgot his reason for being there (to save Eun Ji in the first place). God sent him back to earth but he was at risk to becoming a demon if he did finish his time on earth without resolving his issue. Once he woke up on earth, he noticed he had to hide his wings which we becoming black, meaning his closer to becoming a demon then back an angle. He shoved them harshly into his back and passed out. When he woke up, there were two scars on his back but his wings were secure. He went to find a place to stay or rather set up his box God gave him and sleep in that for the day. He walked around looking for a safe place. He suddenly heard a girl scream in an alley-way shortcut. He dropped his box and went to help the person since he was an angle at one time of course. He used his light powers but away from the girl to save her. He went back to check on her once the bad guys were gone and he saw that he had just saved Eun Ji. She although had no clue who he was. He picked up her nearby phone and looked at the relfection on the screen and noticed that he looked no longer like Taehyung but someone else [Baekhyun from EXO]. He faked a name [Baekhyun] and begged her to stay at her place for a while since he's her savior. She agreed after she heard Baekhyun's fake past story about why he's on the streets now.

Once they made it home Eun Ji was having a sleepover so she locked Baekhyun in her room. That night, she watched a movie about fallen angles who go bat- and played truth or dare. She was dared to sleep alone and she was scared because of the movie so there she slept with Baekhyun on the same bed but no one found out since they never entered her room.

Once they went for the photo shoot, Baekhyun saw EXO's statues, without him of course. They were rebuilding him because he somehow got stolen or something, but of course because he's no longer an angle. 

When they both visit Taehyung's old house, she talks a bit about him and as you could see she was now a weaker character, that's why she kept crying and talked about it only for a little while. When Baekhyun questions the worker