A Professor of Magic at Hogwarts - Chapter 540: Mafalda

Mikail Fremawan, someone who has always been followed by bad luck since he was a child, and the peak was when both of his parents died simultaneously before his own eyes.But the sudden appearance of the System changes everything, from wealth, power, glory, and... revenge; Mikail begins his steps to achieve all of that one by one.Witness his story of turning his misfortune into incredible good fortune.Mikail: There might be something wrong with my System, Isn't it?

Stranded in a world not his own, in a body not his own, Kaden finds himself stuck as a low rank marine in treacherous waters in the middle of an ocean where only the strongest can survive and a count down until a war that would shake the oceans and the very world itself erupts, where the kings of the sea will devour the chum. Gamer System. Insert.

I finally managed to kill the demon lord.

There was a Senior Brother and a Junior Sister. One of them was transmigrated to this world and had cheats while the other was the reincarnation of a Great Emperor.