You are Gilgamesh from the Fate series.

Yagi Izuku had always been beaten and neglected by his so called "friends" and "family". One day, he decided enough was enough and became the King of Curses. #1 - jujutsukaisen #2 - femvali #5 - bitchinko #41 - genderbend

Y/n was a third year at Kuoh high school, he has been dating Rias Gremory since the first year of high school. On the day of there 3 year anniversary Y/n was on his way to surprise His girlfriend with a Expensive Necklace that he was saving up for, But when he gets there he sees his worst nightmare. There he saw his girlfriend Kissing the biggest pervert in School Issei Hyoudou, seeing he two making out passionately Y/n Started crying as he begins the walk back to the apartment in the rain.

Ren, a popular student in highschool, got ran over by a truck on his way home....... Then he reincarnated into the world of "Chivary of a Failed Knight" as the twin brother of Ikki Kurogane

Issei is taken in and trained by the Shinto pantheon. Yeah, this should be fun. Issei x Koneko

Born just minutes after Rias, (Y/N) was always different from his siblings. If the blue hair and the yellow eyes weren't the biggest clues, he was never really liked by anyone in his family except for Sirzechs. But what happens when he, a pureblooded Devil somehow gets a Sacred gear.

Humanity has always lived in ignorance while the supernatural toy and exploit them all on the basis of racial superiority. Despite a few select humans having a way to stand against these magic tossing beings in the form of [sacred gears], they never reach anywhere far before they get killed or turned into slaves of the supernatural beings above them. In this world where humans are treated at best as slaves, what would happen if someone new entered the playing field? Someone with a power long since forgotten....

A gentleman loved by his people and a special girl. During the great battle in which he took part of, he lost his life but an old man from the mountain gave him a chance at life again. He takes up the mantle as the man known as death. It's up to him to maintain peace as the "Grand Servant" to the world. Ps: I'll eventually get good at SD