There are many characters, but these are the main important ones. (Keegle isn't a werewolf, this is the closest I could get to him)
Jake is the main character; He lives with his mom because his dad disappeared to go to Always October, like his own father, Jake's Grandpa. Jake doesn't discover this until way further into the story, however. Jake and Lily are also best friends.
LD gets dropped off at Jake's house by an unknown woman who asks Jake's family via a note to take care of him while she is away.
Please take care of my child while I am away, I will return for him as soon as I can.
He realizes the baby, LD, is a monster that changes during a full moon, and soon receives a visit from Mazrak, a monster from Always October, a place that was supposed to be made up by Jake's Grandfather.
Jake, Lily, LD, Gnarly, Lily's Grandpa, and Keegle end up in Always October because Keegle saves all of them from Mazrak and takes them there. Jake and Lily discover LD is from Always October.
Jake gets caught up with one of the enchanted creatures from AO, a spider named Octavia. She lured Jake to her magical path, but Jake was saved by Gnarly.
The group soon receives another visit from Mazrak, but Keegle holds him off and takes the crew to the AO Council of Poets where Jake, Lily, and Gnarly learn about LD a little more.