Thisismyfirstbooksoitsprobablyreallyreallybad Stories

Isabelle has a boyfriend named Jake. They love each other to pieces, they go on dates and watch the sunset over the ocean. But when it comes to the full moon Jake cancels plans every time. Isabelle doesn't think much of it at first but then she starts to get concerned. What is Jake hiding? Will Isabelle figure it out soon before it's too late?