The Villainess and I, her Zombie - Chapter 569: The Unwanted Revelation

Sue Kirin was a loser. Thirty years old with no hope for advancement at his job and no redeeming features except one, Magic. For as long as he could remember Kirin had dedicated his life to practicing the Arcane. Unfortunately, when he was passing down his knowledge to his niece, she lost control of her power resulting in a backlash of vicious energy that resulted in her being sent to the hospital, her life in critical danger.

The world that nurtured the civilization which reached the pinnacle of magic was on the verge of destruction.
The last survivor transmigrated to the past, when the magic civilization started growing, as countless mages were still fumbling their ways through the thorny paths of magic knowledge.
He, who came from the end of the magic era, aim to reach the pinnacle of magic.

- Description from Novelupdates

Our straight (?) bottom woke up ten years into the future and found himself on the bed of his childhood friend… At the start, the bottom was shocked to his very bones, but he soon quickly accepted this premise and found the whole situation to be rather amusing. Precisely then, the bottom once again went back to his timeline — back to when he and the top were just platonic childhood friends.

Landmines include but are not limited to: Sweet & naive bottom, a president story, logic is dead, slow-progressing romance, the protagonist’s name has too many character strokes, the names are hard to pronounce, too many gay characters…