My MCV and Doomsday - Chapter 682

Beings that create and control monsters and demons, beings that build and reign over malicious labyrinths, the chosen individuals to possess an overwhelming Unique Skill… They are the Demon Lords.

Xia Yan passed through to the world of Bleach and became an eleven-year-old boy. He was rescued by Renji and Rukia in the Seireitei, and he was studying at Shin’ō Academy, and he was a student of the same class.
He is a top student of the Shin’ō Academy, and he is vying for strength by various teams. In the end, he has entered the first team of secret mobile maneuvers.
He will use punishment to kill every person who tries to threaten the martyrdom and protect his loved one.

- Description from Novelupdates

Mizuno Eiji, a siscon high school student, receives the worst news from his older sister: “I have a boyfriend now.”In order to identify the man who stole his sister, he follows her on a date and… sees a suspicious figure watching the two of them as well.That person is Hasegawa Aoi, his classmate who is famous for hating men despite being a beautiful girl!“I can’t believe you are actually a brocon.”“I never thought you are a siscon.”In order to make their beloved sister and brother to break up, the two of them formed a mutual relationship and went on a date as fake lovers while following the brother-sister couple… Aoi kissed Eiji on the cheek.“You’re the only one who is… special.”Brocon x Siscon, two people who shouldn’t be able to get along is actually a perfect match…!?