Reincarnated With the Seduction System - Chapter 15: Sophia Time Part 2 (R-18)

Takebayashi Ryouma, a 39 years old man with hidden past, found himself in a strange white room. The gods tell him that he has died and that they are sending his soul to a different world, a world where magic exists. After living alone for 3 years, his gamer soul loses its common sense and starts along crazy routes.

Before going to college, an ordinary high school student went to celebrate and got drunk. When he woke up, he found himself in a completely different world. There was a big sect, the approaching sect entrance examination, a slum where his body’s previous owner lived, and a shared memory about a missing young girl.

When he got tangled in a fight with a few punks in this different world, he fell off a cliff and miraculously found himself still alive, with two more voices ringing inside his head. They were Sword Master and Saber Master. In the company of them, he continued to find out more about this whole new world. He took the sect entrance examination, entered the sect, met a strange man in black, and even participated in a major competition of the sect to have a chance to win over his peers!
In this whole new world, he was born again and got to explore the fantastic martial world!

- Description from Novelupdates

The boy who Sneaks in My Bedroom Window

In the year 2025, humans awakened with the ability to summon mighty beasts—capable of destroying terrains, breaking the laws of physics, and creating wonders limited only by one's imagination.But before these blessings came a curse.An alien face appeared from nowhere and threatened all life on the planet, leading to the greatest war in human history.In the aftermath, the human race and the alien race were forced into a shaky treaty that could be broken at any time.Years later, tests for summoning abilities began for the next generation. Those who awakened low-grade summoning would be thrown to the gutters, while those who awakened higher got to join great factions after graduating from the academy.Kairos Veyl, the blank, calculating student, pulled his hand from the massive crystal pillar and stared at the large beast before him.“This kid—he just got a LEGENDARY SUMMON.”A legendary summon? The greatest class of summoning. However, with this class came a risk one would have never guessed.