That is Shiva/Shesha Naag(cosmic consciousness)
Reverse of ShiVa(unmanifested) = ViShnu(manifested)
Both are names of same omnipresent,omnipotent,omniscient Brahman, where Lord Shiva is unmanifested consciousness while Lord Vishnu is manifested world.
Brahman and Shakti are one, as fire and its heat, or milk and its
whiteness, are one. When static the reality is Brahman; when active it
is Shakti, the Mother.
Brahman(Heavenly Father/Abraham/Cosmic consciousness) is same as Shakti(Mother/Holy Spirit/Goddess Kaali/Vishnu(Vishwa(world)+Anu(atom)/matter/atom).
Krishna/Vishnu is Kali, this was also told by RK Paramhans several times in his speech.
Shiva represents Sun, what happens when you see a Sun, you close your eyes(unmanifested-Gyan)
Shiva represents Sun with closed eyes with Moon/Vishnu on his head
Vishnu represents Moon
What happens when you see a moon, you keep on looking at his beauty.(manifested-Bhakti)
Lord Vishnu/Moon with the Sun/Shiva as his Sudarshana Chakra
The meaning of the name "Krishna":
"The name Krishna means 'all-attractive.'
The word Sudarshana is derived from two Sanskrit words – Su(सु)
meaning "good/auspicious" and Darshanav (दर्शन) meaning "vision". In
the Monier-Williams dictionary the word Chakra is derived from the
root क्रम् (kram) or ऋत् (rt) or क्रि (kri) and refers among
many meaning, to the wheel of a carriage, wheel of the sun's chariot
or metaphorically to the wheel of time
Lord Shiva(SUN) is for the worship by introvert people like Gyanis while Lord Vishnu(Moon) is for the worship by masses through Bhakti by extrovert people who cant imagine unmanifested, formless Brahman
Kabir das explained by Ramkrishna Paramhans
Kabir used to say: 'God with form is my Mother, the formless God my
Father. Whom should I blame? Whom should I adore? The two sides of the
scales are even.' During the day-time Haladhari used to meditate on
God with form, and at night on the formless God. Whichever attitude
you adopt, you will certainly realize God if you have firm faith. You
may believe in God with form or in God without form, but your faith
must be sincere and whole-hearted."
But both are same eventually and reverse their role, and thats why Shiva is Chandrashekar while Vishnu is Surya Narayan. In short,
Shiva(unmanifested Consciousness) is Father and Vishnu/Goddess Kaali/Krishna(Matter/atom) is Mother(Vishnu means Vishwa(world)+Anu(atom))
Why Lord Vishnu is mother because Vishnu is Padmanabha and only mother gives birth to child from the navel.
Lord Vishnu/Goddess Kaali giving birth to manifested universe/Brahma from his naval, hence he is Padma nabha, Nabhi/Nabi/Guru/first Teacher(Mother is the first teacher of children)/Prophet of the entire universe. hence, he takes avatars like Rama, Krishna, Chaitanya Mahaprabhu to teach mankind.