I am writing a series of five novels, and they centre around four couples. Emily and Daniel, Jake and Yvonne, Cara and Andrew, and Sasha and Marvin. I am so totally in love with the first three couples, and I feel like I really understand them as characters, but I feel like Sasha and Marvin are lacking character development. I don't know if I should just get rid of them or not. I mean, I love Sasha, but I'm not sure if she has a purpose. And I can't really get rid of Marvin, he plays quite an important part, but I don't really like him that much. I'm really struggling with this, I have been working on this project for a long time now, and it is really upsetting me. Killing off a character is one thing, but getting rid of one altogether is quite devastating. These characters have become very close to my heart, so what I'm basically saying is, how do you develop a character well? What should I do in order to understand Sasha and Marvin? I had no trouble with the others.