Answer by Raakhee V. Menon:
I believe that He is very much married.
In all Nair ancestral homes, it was customary to have a serpent grove in the woods around the house. The idols kept for worship in these groves are those of Nagaraja (Vasuki), Nagayakshi and several other smaller idols representing their daughter, Nagakanyaka, and other minor deities. They are all worshipped separately.
Some temples have sculptures and figurines of the Serpent King and Queen together.
Serpents are said to represent ‘fertility’ and that praying to them is believed to be beneficial in begetting children. So it would go without saying that the serpent deities would most definitely have a spouse.