Kumbhakarna continuously sleeps in the Ramayana. He only wakes up for a day after six months of continuous sleep. But why does he sleep for such long periods. As per Ramayana, Kumbhakarna was a giant. He roamed around the universe creating havoc. He caused damage to Devas and humans.
Kumbakarna once performed intense austerities dedicated to Brahma at Gokarna along with Ravana. The tapasya continued for several years. Devas were worried that Kumbakara might become even more powerful and destroy the earth and heaven.
Soon the Devas realized that Kumbhakarna was planning to ask extinction of Devas as boon.
Devas took the help of Goddess Saraswati to thwart the evil designs of the huge demon. She promised to help them.
Finally, Brahma appeared before Kumbhakarna and as boon wanted to ask nirdevata – extinction of Devas. Just as he was about to ask the boon, Goddess Saraswati influenced his speech and he asked nidravata – sleepiness. Brahma immediately granted it. Thus Kumbhakarna sleeps for six months and wakes up for a day.