Toaru Majutsu no Index: New Testament - Volume 9, Chapter 7: “A Normal High School Boy”. Black_or_White.

Lucien's last memory was skidding tires, blinding headlights, the sickening crunch of metal.But that wasn't the end.He lived his life and died an overworked and underpaid, but he rose as Lucian D’Aureville. Incumbent heir to House Aureville, one of the most powerful houses in the kingdom.However it wasn't as rosy as it seemed.His predecessor had been murdered by someone, and they wouldn't be happy to see Lucien alive.Follow along as Lucien navigates the complex and treacherous path of nobility and wealth as he rises to the top.

Once Gu Qingjiu, she was fortunate enough to be born in the “best” family, ended up having a miserable and unjust life.

Reliving her life once more, Gu Qingjiu chooses to enlist in the military and bear the toughest hardships she has ever faced. Everyone says that she’s the least possible person to join the special forces. However, she manages to prove all of them wrong.

Good-for-nothing? Who’s the good-for-nothing? Is she a good-for-nothing when she can throw all of them onto the floor in a fight? Is she a good-for-nothing when she has results better than everyone else? She’ll prove all of them wrong.

Enter Helian Niancheng, the well-known, youngest major-general in Beijing. A banishment sends him into the basic ranks in a military camp as a new recruit. From then on, he meets a person that makes him dote on and protect at all costs, his beloved. However, his beloved is only focused on fighting and killing. Major-general Helian declares this to be a very bad, a very terrible situation. Yet, Gu Qingjiu merely replies,

“Scram! Lower your gun if you dare!”

In the twenty-ninth year of the First Emperor, Bo Langsha was attacked.

When Ying Zheng merged the memories of the 21st century history doctor, looked at the mighty mountains and rivers in front of him, and said to himself, “In this life, my Daqin can’t die!”

- Description from novelbuddy

Being able to see into people's past has no real appeal for the teenager this story is about, letting him use it only as amusement and to show off when he was drunk.Never watch into someone's past beyond a superficial level.Never try to find out more than you should.NEVER. EVER. LOOK. INTO. THE. FUTURE.But everything changed the moment he was forced to look into the future, was forced to investigate a murder, and was forced to make the acquaintance of the victim's twin brother('s fists).The more time passed, the more it appeared that the primary reason for this murder wasn't a local problem, but a global one.This single, marred corpse was the beginning of a threat that would shake the world.(MC looses a screw when he enters the prison)BL, first-person view; MC is shuo (perhaps even a reversible couple); love interest falls in love first; both MC and ML are straight, mutual bending, Enemies to Lovers