I'm Thirsty! (のどが かわいた旅人, Nodo ga Kawaita Tabibito, lit. Thirsty Traveler) is an event in Tomba! 2: The Evil Swine Return.
Bring a bucket of cold water to quench the traveler's thirst.
If you bring some hot water from Pipe Area for him, he will attempt to drink it, only resulting in him screaming in pain from the hot water.
Holy Water from the Water Temple has the same effect as cold water.