My Muscle System in the Mage World - Chapter 334 Nina appears

The backstage manipulator of the Immortal Cultivation World, the sole law in the real world!After transmigrating to the Immortal Cultivation World, Su Ping diligently cultivated for twenty years.Trapped by his mediocre talent and seeing no hope for Foundation Establishment, he decided to lay low and become a wealthy layabout.Fortunately, he activated the Fishing Man game system.Not only could he obtain unscientific and non-immortal cultivation game props, and magical fish species through the fishing game, but also Pot Cave Heavens.He could even exchange his fish catches for Town Return Talismans, allowing Su Ping to return to Water Blue Star.Thus, the Immortal Cultivation World henceforth had a self-proclaimed Fishing Man as the backstage manipulator.And Water Blue Star gained a backstage boss who followed no rules but his own!

Vincent Strider was a gun for hire who made a living by killing whoever it was his clients wanted dead. But during one mission, he died in a fierce gunfight. However, death was not the end for him. Vincent found himself reincarnated in another world, facing a floating interface that flickered before his eyes.[Synchronizing Host!][Military System initializing.]Vincent found out that in this system he received, he can summon soldiers, tanks, aircrafts, and even warships! This is going to be exhilarating.

He is a young man without a spirit root. It is believed that this denies him the chance at cultivation. However, a mysterious lady imparts a Supreme Demon Classic to him and from then on, he starts his path of cultivation.
He undergoes a total transformation to emerge as the most fearsome and powerful fiendish demon in his era, that even immortals and fiends are fearful of him, and saints are at his beck and call.
Mastering the Supreme Demon Classic is the turning point in his life. He is able to unleash his immense and divine power from within, illuminating the entire universe!

- Description from Novelupdates

After dying in an oddly anticlimactic vending machine accident, Kazuki Ren is reincarnated in the demon realm—not as a hero, not as a villain, but as the only human male student enrolled at the mysterious Academy of Ruin, a school where all the professors are demon lords and all the students are powerful, beautiful she-demons.Ren is told he has one task: survive.But there’s a catch. The Academy’s darkest secret is about to awaken, and Ren holds a hidden power that could either destroy the demon world... or rule it.Now surrounded by seductive demons with hidden motives, eldritch tomes, forbidden dungeons, and twisted exams, Ren must master his ability—or be consumed.Magic, mystery, danger, and temptation await in this dark academia harem fantasy.