I feel in love with Max after the first line:
"Max had been a cat as long as he could remember, but he was pretty sure he'd been a rock star in one of his previous lives."
That just about sums up Max's personality. He is an amazing character, and half the book is told from his perspective. The only thing he loved more than himself was Melody, and he figured she needed a man and he was the perfect person (errr cat) to help her find one. So off he goes and has quite an adventure, bringing it home to share with Melody.
Melody is a very quirky and unusual person. She's a children's librarian and is often caught out whilst dressed in costume for that day's story time. Max is the current love of her life and when he goes off for his wander she gets very upset and worried. It was awesome to watch the two of them related to each other and at times lovingly completely misunderstand each other as well.
There is more than just a fun cat and a quirky girl in this or it wouldn't be much of a romance. The romance brings with it just a touch of drama and secrecy that comes very close to ruining the whole thing, but somehow Max jumps in a saves the day again.
As a novella you could fly through this book in one sitting, and I recommend doing it that way because you won't want to put it down. While Max is definitely the life of the party here, the romance is also beautiful.