Concept: a bunch of high school Satanists get drunk in the local graveyard and try to conjure a demon, but they’re using one of those “reconstructionist” ritual books that gets its sources all mixed up, so they end up with a minor Mithraic fertility spirit that hasn’t spoken with humans in like 1700 years instead. By the terms of its binding it’s not allowed to leave until it’s ensured a successful harvest for its summoners, which is a problem, because none of these goobers have ever raised so much as a houseplant; if it wants to go home, it’s going to have to teach them how to garden – whether they want to learn or not!