Transmigrated Become Sukuna, but the host is Yukinoshita Yukino? - Chapter 150 - : Life and Death

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.

The Student Council President’s Secret Laid Bare (生徒会長のセキ裸ラな秘密) is fairly standard 2D Dream Bunko fare but with an exhibitionism theme.

Basically, it’s about a guy who discovers the student council president is an exhibitionist and gets roped into helping her with that fetish.

Qin Chen crossed into Taiyi Holy Land as a sweeper, and at the age of sixteen awakened the system. As long as he signed in at different places, he could get different rewards.

Sign in at the Land of Emperor Ruins and get the world’s No. 1 Chaos Holy Body and the Chaos Emperor Sutra!

Sign in to seal the magic land and get the quasi-emperor soldiers!

Sign in at the Refining Hall and get the God-level Refining Technique!

Sign in at the medicine garden and get the medicine of immortality!

Sign in at the Imperial Palace and get the Emperor-level forbidden magical power ‘Resurrection from the Dead’!

…

Qin Chen thought that he would just sign in silently until the world was invincible.

One day, the relics of the Great Emperor will appear in the Holy Land, all the holy places, families, and ancient dynasties have come, and there will be an unparalleled demon king in the relics, killing countless powerhouses, ruling the world, and wanting to destroy the Holy Land.

In desperation, Qin Chen could only walk out, slapped the Demon King to death, and sighed: “I just want to be a sweeper and sign in silently. Why do you force me to take action?”

- Description from novelbuddy

[You have entered the dungeon at Gwachun Station’s 1st Exit.] When former high school student Kang Woojin finds himself returned back to Earth after being forcibly summoned to a foreign planet for 20 years, he soon finds that Earth is not the same, normal place as he once remembered it to be.