The Night Beast is Annie Howell. You can find her in the Nighthowl Saloon. But, you have to build a tazzer first though. To build a tazzer, you need a four mechanical skill points, and spare parts where you can buy from Pita Florica, who sells goods in Deadtree. Once you've built the tazzer, go into the Nighthowl Saloon, and find Annie Howell. Then tak the tazzer and zap her. She'll transform into the Night Beast. Then, to advance in the game and complete a goal, give her $700 dollars for Anger Management Classes.