Look, if you don't know what this is, play the original monster prom. It's not necessary to follow all the non-sequitur glory going on, but if that doesn't appeal this probably won't either. That said: If you did enjoy it, play all of these. Writing quality is consistent, the nonsense is glorious, the art is fun and The characters are lovable dorks.
This game, which I first experienced on the first Playstation as a kid is responsible for (at least) the following: - My growing interest in the art of voice acting. - My tendency to side with characters voiced by Simon Templeman, regardless of how evil they are, if only to get the maximum amounts of spoken dialogue delivered by him. - A love of villain protagonists. - An interest in video games with a story. - A tendency to look up video game soundtracks. - Not apparent in this part just yet, but this series is one of the few narratives ever where I felt the time travel aspect was handled in a truly interesting manner.