My Genius Sister is Only Seven!? - Chapter 15

I, Zatiel, Abyssal Lord, Ruler of Death and Destruction, Nightmare of Dys, have AWOKEN!!!!!.

His life contains events that can shake the universe:
-Fighting against Tiamat, Creator of Evil Dragonkind, in the first circle of hell, while billions of demons and devils butcher each other beneath them
-Start a World War against the Heavenly Race, and transform himself into a Golden Sun while he slaughters their greatest warriors, the Archangel.
-Enter the Final Gate and fight against the Outer Gods.
-Tearing the nine levels of Baator during his battles against the Prince of Evil, Asmodeus.

With his memories as a ruler of the Abyss and a Universal Existence, Zatiel will rise again.

Kōdo Ikusei Senior High School, a leading prestigious school with state-of-the-art facilities where nearly 100% of students go on to university or find employment. The students there have the freedom to wear any hairstyle and bring any personal effects they desire. Kōdo Ikusei is a paradise-like school, but the truth is that only the most superior of students receive favorable treatment.The protagonist Kiyotaka Ayanokōji is a student of D-class, which is where the school dumps its “inferior” students in order to ridicule them. For a certain reason, Kiyotaka was careless on his entrance examination, and was put in D-class. After meeting Suzune Horikita and Kikyō Kushida, two other students in his class, Kiyotaka’s situation begins to change.Note:- Even though Volume 0 is the prequel of this series, it is advised to read till Year 2 Volume 8 beforehand to avoid getting spoiled (which is precisely the reason why it was released after Y2 V8).Anime:-Season 1: Volume 1 to 3 + Volume 4.5Season 2: Volume 4 to 7 + Volume 7.5Season 3: Volume 8 to 11 + Volume 11.5

His fiancée, whom he had never met, had just broken off their engagement. He's then betrayed by his girlfriend and schemed against by her lover.His mother's legacy awakens him. No longer content with mediocrity, he transforms into a dragon overnight.

Qin Xiaobai transmigrated into a husky.
And his master turned out to be a goddess-level live broadcast.
Reporter: “Miss Su, you are now the first sister of Douyu. What’s the secret of your success, is it your good looks or hard work?”
Su Wanqing thought for a long time, then pointed to Erha beside her and replied, “It doesn’t seem to be the case. The main credit for my current achievements is that my Erha is so outstanding! Sometimes I even doubt that my Erha is the protagonist. …”

- Description from novelbuddy