Mattheus was the first fairy to be conceived and born the human way. Before his mother fell in love with another fairy, fairies were only born from special flowers once every hundred years, and they were pretty much fully grown when they emerged from the petals.
So Mattheus not only had to deal with being the first Fairy baby, he was an only child for over a century before his brother, Sebastian, was born.
He has been searching for his compatible soul for so long, knowing she would be with him for life, to help fill the void inside him. He started traveling to the human world when Sebastian made friends with the witches, and met Alec at a witch bar where Alec helped him get laid.
Mattheus later met Ari, Pierce's oldest sister, who left him after they discovered they were mates. He then set on a quest to find her and bring her back.
Neck-Romancer: It's a Wonderful Jaz