Tokyo Paranormal, the beginning reminds me of the game plot

On the day he received the admission letter from Onmyoji Academy, Taichi Yagami recalled his past life memories and found himself traveling into a galgame, becoming a miserable tool who helped the male protagonist conquer the female characters.
In the first two years of college, the self in the game was the male protagonist's friend and provided him with a lot of information about female characters. In the last year, due to the awakening of the blood in his body, his personality was formatted and he became the resurrected body of the legendary monster "Yamata no Orochi", and then helped the male protagonist to capture the last girl.
Taichi Yagami doesn't want to be a tool, and he doesn't want to die easily.
Fortunately, the God Rewards Hard Work System appeared at the right time. As long as one becomes a Pure-level Onmyoji before his bloodline awakens, one can avoid a tragic future.
At this point, the academy has one more hardcore player.
Hundreds of spiritual arts, bloodline fruit, soul weapon, shikigami contract...
And with the awakening of Taichi Yagami, the original story has undergone earth-shaking changes.
This book is also known as "My left hand Bankai · Heavenly Fire Holy Judgment, my right hand Ice Release · Demon God Appearance, and the God of War Greymon is following behind me, what can you use to fight me?"