The Neckless Troll is a lazy friend of the protagonist. He wears a black jogging suit because he thinks it has a slimming effect. It shows his poor hygiene, mostly due to laziness. He is a bad friend whom the protagonist must eventually shed if he rises above his problems.
Jessica is an actor. She has worked with the protagonist before. She enters the movie as an actor being filmed in a low budget movie, but after the protagonist calls "Cut" she is revealed to be his long-time confidante. As they commiserate, there is a short love scene, but it is decided that they may ruin their working relationship. That love scene is initiated by Jessica, and it seems to promise a beautiful crescendo, but the protagonist soon turns it into a goofy catastrophe.