Alpha's Rejected Mate Returns as Queen - Chapter 555 - : The Rising Sun

After dying in an oddly anticlimactic vending machine accident, Kazuki Ren is reincarnated in the demon realm—not as a hero, not as a villain, but as the only human male student enrolled at the mysterious Academy of Ruin, a school where all the professors are demon lords and all the students are powerful, beautiful she-demons.Ren is told he has one task: survive.But there’s a catch. The Academy’s darkest secret is about to awaken, and Ren holds a hidden power that could either destroy the demon world... or rule it.Now surrounded by seductive demons with hidden motives, eldritch tomes, forbidden dungeons, and twisted exams, Ren must master his ability—or be consumed.Magic, mystery, danger, and temptation await in this dark academia harem fantasy.

Yeho is a distant relative to a king in a small kingdom. Even though he is a distant relative, his house was very poor, and his mother was addicted to gambling. One day North Empire asked for Princess Sooyoung to be a concubine of an old Emperor because she was known for her beauty. But the king really loved his daughter so instead he ordered Yeho’s older sister to disguise as Princess Sooyoung and marry the old Emperor.

Yeho told his sister to run away with her lover, and his sister had to leave her younger brother alone with his mother. After she ran away, Yeho asked his mother to give the things back to the king that she got for trying to sell her daughter, but his mother already used the gifts to pay off her gambling debt. He was trying to give the gifts back to the king to take away his order, but now he can’t do that anymore. He tells his mother to run away, and he disguises as his sister to go to North Empire.

After he got there, he was trying to tell the Emperor the truth and take away his life, but the Emperor went out for few days to look around his empire. When the emperor came back, he wasn’t as old as he thought.

The two faced number one female spy transmigrates to a different world and becomes an outrageous idiot girl. When she woke up, what she had to face was consecutive blows of the decline of her family clan, her crippled martial skills, and her disfiguration. To protect her family, she must obtain the treasured book, obtain outstanding achievements, summon a dark beast army. Wait and see how in this unfamiliar, dark magical continent, she dies and becomes a demon then steps up to the top, making all of the formidable people in the world bow down to her in respect.

- Description from Novelupdates