Paul-Clay is Max-Ernest's little brother. He, like Max-Ernest, has two names because his parents each wanted to name him something different. His father insisted on Paul, and his mother Clay. To Max-Ernest, Cassandra and Yo-Yoji, he is known as PC. His parents both read manuals on how to care for Paul-Clay, insisting they would "fix the things they got wrong with Max Ernest", but could not decide on one name. It is said that Max-Ernest is acting as PC's parent.
Paul-Clay is known as just "Clay" in the book Bad Magic, of which he is the main protagonist. He does this because it reminds him too much of his brother Max-Ernest since they both have double names. (For more about the book, see the page on Bad Magic.)
Paul-Clay most likely will look like Max-Ernest. Because he is a baby when the series ends, it is not known what he will look like.
Later it is known that he usually jiggles his leg because like Max-Ernest's probably with not being able to stop talking, he has a problem with not being able to stop moving. In pictures, he is shown to have messy, dark hair and usually wears shorts and a T-shirt as well as a hoodie so that he can conceal his face.
In the beginning, Paul-Clay seems to be really close to his older brother Max-Ernest. He spent a lot of time with him performing, learning, and watching magic tricks with him. When Max-Ernest disappears, though, Clay get mad at him because he thinks that his brother ran away from his family because he hated them.
At the end of Bad Magic though, it is shown that Clay is about to cry after reading the letter he received from Max-Ernest.
Leira is a girl that Clay meets on Price Island during summer camp at Earth Ranch. He hates that she always pickpockets something of his, usually his wallet. It is possible that he has a crush on her because when Jonah, Pablo, and Kwan mention that they think Leira has a crush on him he begins to blcsaush. And after this, he tries to become friends with her again after she hears what he "really" thinks of her after she accidentally overhears him while once again taking his wallet. (It is also possible that she takes his things as a way of flirting with him.)
He also seems to like how Leira was worried about him after he hit his head during his swimming test. She later helps him as he tries to figure out the mystery of Price Island. \
Clay hates Flint just as much as Flint hates Clay, even though Clay is interested in Flint's pyro-magic.