The acting is great but that's the only thing I like in this movie.
In my opinion, a story like this is very unrealistic. Also the moral of this story is to show that the outer appearance of a person doesn't matter...it's what's inside that does. But I don't see that message being delivered properly either. They don't really show what the two leads actually liked in each other. All they seem to talk about and bond over is furniture. We don't get to see their proper personalities.
And anyway how can she deal with him looking old enough to be her grandfather or young enough to be her son?? O.o Creepy.
Also if the whole point of the movie is that the outer appearance doesn't matter, why are there intimate scenes only when Woo Jin is a good looking man? So yeah I don't get the point of this film.
Plus, it's just too weird for me. Woo Jon's appearance changes every time he goes to sleep...there's no limit to the gender, race or age. I just can't imagine anybody being able to marry someone like that. Being a friend is different. Can anyone marry someone like that and deal with all the gossip and the inevitable stress?? It's too unhealthy and creepy.

I felt the same way after reading the book "Everyday" by David Levithan (I didn't watch the movie). That book too has something similar to this movie and I didn't like it much either cause it was too strange. :/

1 point for the good acting.
Another point for the good directing.
And .5 for the music.