So I know I haven't update recently, but I need to clarify some things before I continue with the story. 

Ok, the story is about what happens in dreams, ok? All the things that happens with Kyungsoo is a dream, all the talks and basically everything... yes...

When she (or they) sleep in the real world she wakes up in the dream land, if you want to call it that way, they eat, watch movies, all the things they can do in real life, but they only can do it in the room they are. When they sleep in dream land they wake up in real life.

She can't remember her dreams because she have some kind if trauma, you can read it in the letter his father let her.

In the last chapter I explain some things

-when you(she/he) sleep with stress, pills or something that is  different to the natural process of sleep they don't appear in the room they usually are. Different process, different place.

-they can do whatever they want in the room and is going to be there the next time because is another life in a dream, thats why when she gives him the present she said that she got it before.

-kyungsoo find her room some night that he was dreaming some strange things and was running out of it, since then, the lived together in her room. I liked the idea of her room because in the future is going to be pretty that he knew the room and when she.... ok that is for later...

After she read the letter of his dad, she start to 'remember' things she don't even know she had in his mind, she thinks that she read it in some book or saw in a movie. That is basically what happens in the store with the old lady.

Oh, yeah he remember everything about her, every single moment that is sad really, she don't... haha

I know my english , but I don't have a computer, that is why it is so ... so, ugly and I can't fixed either because is difficult in my cellphone. Sorry!

You have another question?

I hope I help you to understand a little...