Su Lun and his companions were making rounds just outside the city.
They had also discovered that Princess's aura could not be hidden at all. The living yang energy repelled by the entire Netherworld was like a beacon of light in a dark world. No matter how much they tried to conceal it, even a leak would attract monsters from afar.
So, even going to the Asakusa Temple, the monsters would relentlessly pursue them.
The Shroud of the OZ Ice Man that Su Lun had could completely conceal her aura, but the cursed property of this sealed item was life consumption—using it might be worse than not using it at all.
There likely wouldn't be another chance to receive a mud pellet from the "Beggar God."
Hence, under normal circumstances, if they didn't split up from the Princess or stayed in one place too long, they were at constant risk of being caught up by monsters.
Moreover, the corrosion of the nether energy was a big problem.