Harry Potter: The Legend of Nero Ravenclaw - Chapter 5: Rank is Power

I was reincarnated into another world, and I’ve brought the Horadric Cube from Diablo II with me.
Being a knight is cool and all, but being a wizard is pretty neat as well.
So, which one will it be?

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

Many islands dotted the vast oceans of this world. However, some of the islands were a lot more sinister than the rest. Those islands, known as Nightmare Islands, were true nightmares to all but the strongest and most fortunate. Children were kidnapped and thrown on these isolated islands by the Nightmare Palace, forced to sign soul pacts with evil soul pets: Nightmares. These devils slowly devoured the souls of their trainers to grow stronger. If the children did not cultivate fast enough, their souls will be devoured whole, leaving only an empty husk behind.

Chu Mu, the protagonist, was an heir to the Chu Clan, but due to a plotted murder, he was thrown on the island, sentencing him to almost certain death. Dancing on the edge of life and death, he struggled to survive with a small Moonlight Fox he captured. When he finally escaped the devilish foremen on his island, he couldn’t help but let a breath out. But little does he know, the experience was only a beginning to a fated journey with his little Moonlight Fox…