Full-Time Magister: The Failed Knight, But the Dark Angel

[Incredibly satisfying and exhilarating story] [Fast-paced]
Mu Ningwei, a member of the Mu family in Shanghai, was taken in as a disciple by Wen Tai when he was young. After studying at Parthenon, he returned to China.
The Shadow element can connect to the Dark Dimension and summon Master Wentai, who has become the Dark King and is a walking Dark Angel.
The Light System can connect to the Dimension of Light, hear the whispers of Athena, the mother of the gods, and be followed by Holy Light Unicorns.
"Darkness and light are both mine. After you die, do you want to ascend to heaven or fall into hell?"
"Oh, I forgot to mention, I am invincible in the human realm."