Sovereign of the Three Realms (WN) - Chapter 2336: Heavenly Crimson Lake

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.

A tale of transporting to an alternate world! Let it be so, but why did she turn into a dragon?

As the last dragon in this world, Yi Longlong became the target of the dragon knights, but why are they competing on who gets to ride on her back?

She’s only a young girl who hasn’t even been on her first date!

Are good looking men so remarkable? Just because they’re good looking doesn’t mean they can ruin this beautiful innocent girl… Dragon?!

- Description from Novelupdates

Amakawa Haruto died before he’d the chance to reunite with his childhood friend who disappeared five years ago. Rio, a young boy living in the slums seeks revenge for his mother who was murdered in cold blood in front of him when he was only five years of age.

There exists the earth many knows of and there exists an alternate world. Two people, each with their own backgrounds and values. For odd reasons, the memories and personality of Haruto, one who should have died resurrects in Rio’s body. As the two are confused over their memories and personality fusing together, Rio (Haruto) decides to live in this new world.

Along with Haruto’s memories, Rio awakens an unknown but special power. If he’s to use it, it looks as if he can live a better life, but before that, Rio encountered a kidnapping which results in involving the two princesses of the Bertam Kingdom.

After saving the princesses, Rio is given a scholarship to attend the Royal Academy, a school for the rich and powerful. His background being a poor orphan who once lived in the slums, the school full of nobles was rather a detestable place to stay at.

Yun Xiangxiang was a well-regarded celebrity in her previous life.