Edward watches Bella sleep because he is drawn to her, both emotionally and physically. He is fascinated by her vulnerability and sees it as a sign of her humanity, which he finds endearing. It is a way for him to protect her and ensure her safety, as he can detect any danger approaching while she sleeps.
because he loves her
Because Edward likes to watch Bella sleep
Edward sleeps with Bella, because he loves her.
Watching Bella sleep...
Romeo and Juliet
He watches Bella sleep sometimes
The first night that she knows Edward is there in her room with her.
Bella: No bed? Edward: I don't sleep. Bella: Ever
I'm not sure exactly what you mean but... he did get in her house and watch her sleep for a while so he probably might have looked around a bit.
In the Twilight series, Edward and Bella officially consummate their relationship in the fourth book, "Breaking Dawn," after they get married.
romeo and Juliet
He writs a Lullaby for Bella. Called, Bella's Lullaby. He plays it all the time and to help her sleep he hums it .