Supreme Casanova: Ultimate Harem System - Chapter 4: Freshman Party.

As monstrous invaders ravage the world, Ryzen Kael— a man shattered by a tragedy ten years ago— faces his final moments. But just as death closes in, a mysterious system awakens within him, offering a path beyond his limits.Now, with nothing left to lose, he steps into a dangerous journey of survival and power, defying fate and unlocking abilities beyond imagination. Follow his rise as he challenges destiny itself, carving his name into history!Author's other storiesThe Unrivaled Holder: Rise of the Dragon Monarch - 3rd Season Ongoing

In the beginning, when they all thought that she was “he”….

ML #1: We will be brothers for life!

ML #2: This time I’ll reluctantly let you have the #1 seat.

ML #3: I will properly repay royal teacher!

ML #4: Ah Rong is my closest little brother, I trust him.

Afterwards…

MLs: I’m seriously such a fool.

MLs: What do I do, I think I’m gay. I fell in love with my bro/rival/teacher….

Afterwards….

MLs: I’m straight! As straight as steel!

Note:
MC is a girl crossdressing as a boy, she knows how to fight, and naturally possess the gold finger halo from the author.

All the ML(s) is the same person, 1v1, sc, HE

- Description from Novelupdates

When he returned to the World of Martial Arts, the game was filled with blood and battles! Chen Kaixin had chased after the footsteps of the one emperor, two empresses, three princes, seven dukes, and thirteen aces for three years, but during the eve of the Sword Among Us tournament in Mount Hua, he was ambushed by evil bastards, and was killed so much that his level dropped to that of a newbie. He completely lost the chance to join the ranks of the powerful players in the game! In great disappointment, Kaixin quit the game and got drunk so that he could forget his sadness, but during that stormy night, Chen Kaixin found that he had actually dreamed for a total of three years, because when he woke up again, he woke up to three years ago, when he was still a student.

- Description from Novelupdates

Transcending to the Otherworld, with the power of unique Attributes, to become the ultimate sovereign.Welcome to my world....Accidentally transported to the vast and boundless world of immortals and heroes, where the strong are revered and immortals and demons coexist.MC discovered that he possessed a peculiar attribute ability, which enabled him to quickly rise on the path of cultivation.With this talent, I have gone through numerous challenges and trials, constantly breaking through my own limits, mastering unparalleled immortal techniques, refining incredible artifacts, and forming an unbreakable bond with many immortal warriors and powerful individuals