Monstro Town is a location in Super Mario RPG: Legend of the Seven Stars. It is home to more friendly enemies in the game like Piranha Plants. It is also home to Jinx and the The 3 Musty Fears and leads to Culex.
Monstro Town is a fairly small town. Jinx's house is located to the far right and a Save Block is found hidden in the southeast corner.
Mario can fight Culex at any time but he needs the Shiny Stone first. Mario must head back to Moleville and buy fireworks (which cost 500 coins) from a mole. Then Mario must give the fireworks to a small mole girl and she will give him the Shiny Stone. Finally, Mario must use the Shiny Stone on the sealed door and he can fight Culex.