My Sister, the Serial Killer follows Korede, a nurse in a Lagos hospital, who also happens to regularly have to help clean up after her sister, Ayoola, murders her boyfriends. When Ayoola starts flirting with Korede's own crush, a doctor at her workplace, Korede has to decide who to protect.
Now, this book was well written, but I felt a bit let down by the description. There was a few funny lines, but I wouldn't have called it 'full of deadpan wit', and it definitely wasn't as thrilling as I was hoping for.
I enjoyed most of this book, watching Korede realise that quiet resentment of her sisters behaviour is not going to be sufficient to protect Tade, and watch her battle with her loyalty and knowledge of how her sister would respond to knowing her feelings. I thought the relationship between the sisters was well developed, but over all this book suffered from how short it was. Aside from the sisters history, there was little development of the characters. There was discussion of

the abuse their father inflicted

but no real discussion of why that was important in their story. 
Additionally, I didn't love the ending. I don't mind that she

chose her sister over Tade

but I do mind that there was no exploration of the repercussions of this. The end felt abrupt, and I would have liked to see a bit further into the future.

Does Ayoola continue killing, and Korede more 'officially' help her? Does Ayoola understand the choice Korede made or does she just continue on, oblivious?