Academy's Pervert in the D Class - Chapter 6: “W-Who’s there?”

After discovering about her wealthy husband’s affair, she humiliates the adulterous pair on the streets and divorces him the very next morning. Just as everyone anticipates her downfall, she goes on to marry the most brilliant bachelor in the nation whom her unfaithful former husband cannot hold a candle to!

agreed. He thought they might just talk, have a few drinks, and that nothing significant would happen. However, she invited him to a hotel, and they spent the night together.The next morning, she told him it was just a one-night stand and that they would probably never meet again. She said goodbye and left. Ronan also decided to treat it like that.The next day, at his college's hosting club, Ronan was given the responsibility of hosting that year's annual function, where they had invited a singer.When Ronan looked up at the singer, he was shocked—it was the same woman he had spent the night with. After checking her history and social media, he formed an impression of her. Every picture she posted was in revealing clothes, bikinis, or almost nude outfits.He concluded that she was just a promiscuous woman, likely driven by lust, and that she had probably chosen to spend the night with him simply because she found him handsome.Understanding this, Ronan decided to focus on his work. That morning, she had made it clear that it was just a one-night stand and nothing more. He would treat it exactly that way and carry out his responsibilities.Protagonist has System---No NTRIt's Harem, with many girls but The Singer is Main Heroine.

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

A former sporting rifle shooter genius transforms into the ‘Juvenile Butcher’. While originally supposed to have received the death penalty, he was instead fortunate enough to have entered a secret and highly regarded armed force, throwing himself into the ‘Nirvana Project’.