The La Lunga is the "Egg Eater". A creature that normally resides in Nayug, the La Lunga is able to crossover in Sagu on occasion. Though only one La Lunga appears in the novel, the anime depicts multiple La Lunga attempting to attack Chagum, the host of the water spirit's egg.
Its diet is largely unknown, but it will pursue and attempt to devour the egg of the water spirit when it is reborn every hundred years or so. It is not believed to exclusively feed on the eggs of the water spirit; rather, it is thought that the egg is likely more of a rare treat the La Lunga will be able to consume.
The La Lunga's greatest influence upon Sagu occurs during the birth of the Water Spirit. In order for the water spirit to be born in Sagu, the egg will appear in a host within Sagu, neither of which will be harmed La Lunga in Sagu. However, in order to be born, the host must consume the nectar of sig salua flower, which leaves the host and egg in a state of liminality between worlds and vulnerable to the La Lunga.