From Angry Fox Scans:
The story is about the Himenokouji twins named Akito and Akiko who got separated due to certain circumstances and after years of living apart they suddenly began to live under the same roof once again. Things were fine at first until Akiko began expressing her love for her older brother. Now Akiko must fight to defend her extraordinary love for her Onii-chan as she battles against all odds and three other girls who are after her beloved Onii-chan.

Goshūshō-sama Ninomiya-kun's story revolves around Shungo Ninomiya, a male high school student trained in difficult hand-to-hand combat. He lives in a huge house with his older sister Ryōko, who is almost always gone on some dangerous mercenary mission. One day, his sister sends Mayu and Mikihiro Tsukimura, two siblings, to live with him to help Mayu overcome her fear of men. Unfortunately this is accomplished by making Mayu and Shungo share the same room, bathe together and even sleep together in the same bed. Making things even worse, Reika Hōjō, the student-council chair, is blackmailed into becoming their maid due to a video that Ryoko recorded, in which she tries to seduce Shungo. ~from Wikipedia

Fail-translated from the official summary:
Kanaruzawa Sekai, "The God Who Lived A Thousand Years", is a beautiful girl with silver hair and red eyes. She's pompous and does not know much about her surroundings, and despite her childish appearance, she can tolerate alcohol and tobacco, and spends her day in her mansion reading books.
Offered to her as a "living sacrifice" is high school student Kirishima Yuuki. As he was told she'd grant him one thing in exchange of being the sacrifice, Kirishima said: "Kanaruzawa Sekai-san, marry me."
And so, they start to live their life together---but their days without peace nor love became disrupted, as the world began to be disordered due to a terrifying secret concerning the whole world.
A comedically pure love, and a never-ending story begins here!
The comicalization of the light novel "Monku no Tsukeyou ga Nai Love Comedy" starting right away!

//description form jCafe

Based on a true story, this manga's focal point is Modus Operandi and Crime. It's a story about a group of teenage thieves in a reform school who target assailants.

In response to abuse, Kazuki spent time in a reformatory school.
The group, Takeo, consists of three "psychedelic" people who have specific targets: criminals of "assault."

Kazuki—genius of the tool Kimootadebu and leader of Takeo; Twink—Information Analysis Psychedelic and Target-Selection In-Charge; Giants—the superhuman strength of Takeo and Vehicle Maneuver In-Charge.