This book is very confusing at first. Candace calls her other personalities her sisters, so that was confusing. Then each personality has a different voice, which isn't confusing after you've gotten use to it but it was really odd when Candace stopped talking in the middle of a sentence and Shiro took over (which started a new chapter). That doesn't happen all that often but I do wonder what everyone near her is thinking when the tone of voice changes.
I didn't like Patrick all that much. I don't hate him either, but there was something about him that annoyed me.
Shiro's point about integration was a good one and something I'd never thought about before. Is re-integration of separate personalities murder? From that (those) personality(-ies) standpoint, it must be.
Adrienne's chapters are all like poems (or nursery rhymes) which adds another layer of confusion when she first shows up.