Toaru Majutsu no Index - Volume 11, Chapter 2: The Preparations for going to London. Un_Frammento_di_un_Piano.

Jiang Bai woke up one day and found with shock that he had transmigrated to a parallel world that is similar to Earth. There, he was granted a cheat system to help him forge the path of a tyrant in this new world. He was now stuck in this parallel world body, the body of a weak and cowardly person. Join Jiang Bai as he rose to the top in this new world!

- Description from Novelupdates

Some say reincarnation is a blessing, but for me, it's a dreadful curse. Cursed with endless reincarnation, I've been reborn as a villain 137 times. And all 137 times, I've been toyed with and killed by heroes who are far more cruel than the said villains... If I can't win no matter what I do, then I'll crush those so-called heroes at their very roots. - Quality Fan Translations, Made by Fans for the Fans - Villain Takes Over The Academy

A 20 year old young chef, Kai, loved Supernatural things. He loved to read and know about myths and stories and longed for them.

One day, after closing a restaurant, a voice called out inside his head.

[Help me!]

What he didn’t know was his life would change when he met a girl, a Phoenix, who asked for his help. From her, he found out about his special constitution of being able to make a contract with Mythical Beasts.

With the power of Mythical Beasts in his hand, he would shake the hidden Supernatural World.

Accompany his journey, from being a simple cook to the Mythical Slayer accompanied by a few Mythical Beasts (Girls)!

The first great emperor in the world was betrayed by his confidante and perished. Millions of years later, the great emperor’s soul returned and was reborn as Ye Yan, the son-in-law who was kicked out by the Chu family with a letter of divorce, restarting the supreme journey. Open the gate of immortality, kill the Jiuzhongtian, and cast an invincible name again!

- Description from novelbuddy