For the bit about brain worms being plot important? If so, yep! It’s pretty much the premise of the intro; you’re kidnapped by Lovecraftian-esque beings called “mind flayers” who take you aboard their organic spaceship and have one of their tadpoles wriggle into your brain. Hijinks ensue, and can include tough choices such as “do you resist your violent urges or cut off the funny magic man’s hand?”, “should you condemn a child to death because they committed petty larceny?”, and “do you want to have fuck with the bear?”