Fortunately for the Slimelord, their kind are masters of disguise. It turns out you had been dealing with the Slimelord for the entire original game without realizing it because the Slimelord was actually... KING LORIK!!! The real king was killed and replaced shortly before the start of DW1. This explains why "King Lorik" is so focused on killing the "evil" Dragonlord that he hardly seems to care that his own daughter is missing.
So things are in pretty bad shape at the start of DW2. The good Dragonlord is dead, and Slimelord controls all. But don't despair! Gwaelin holds another secret. Before Erdrick died in that Elf Village from Final Fantasy, he had his consciousness transferred into the body of a robot (also from Final Fantasy) and arranged to have himself disguised as a princess and adopted by King Lorik. This way, he could keep an eye on the kingdom forever without being too conspicuous.
Now that the Slimelord is in control, and the hero from the first game was killed and ripped apart by a party of Drakees some time ago, it's up to Princess Erdrick to save the day. Did I mention that robot princess Erdrick was cursed by this game's other villain, Platinum-Man-Lord?
Dragon Warrior II: Slimelord and a Cursed Robot Hero Princess

