Have you heard of Hell Correspondence? Those with a powerful grudge may only access this mysterious website at midnight, allowing them to enter anyone's name and have that person be ferried straight to hell. Ai Enma, the Hell Girl, will not judge whether or not the chosen target deserves punishment; she will merely exact revenge on them for you. Not much is known about this young girl other than that she swiftly carries out her tasks with the help of three straw dolls. There is just one catch, however—as payment for carrying out such a request, the user must condemn themselves to an afterlife in hell. [Written by MAL Rewrite]

There isn't a single person in Sakuradamon High who hasn't heard the legends about Seiji "The Mad Dog" Sawamura's demonically powerful right hand. His reputation makes it fairly difficult for him to approach girls, and after being rejected 20 times straight, he half-jokingly vows to finish high school with his right hand for a girlfriend. Much to his surprise, after waking up the next morning, Seiji discovers that his demon right hand has mysteriously turned into a miniature girl, Midori Kasugano, who reveals that she has had a crush on Seiji for the past three years. Because their situation is not ideal for either of them, Seiji attempts to return Midori to normal. But after causing a big misunderstanding at the Kasugano household, the pair decide to keep their predicament between them until a solution is found. Thus begins an odd relationship, and what could be the only chance for Midori to finally be with the one she loves. [Written by MAL Rewrite]

Sousuke Kaburaya, an impoverished detective, meets Sara, a princess from another world with magical powers. They start living together, and Sara quickly adjusts her life to modern Japan.

Five years ago, a string of grisly murders shook the city to its core and now the rumors have begun once more. Boogiepop... Everyone knows about Boogiepop: meet her one dark night and you are taken. People tell each other the stories and laugh: no one believes that she can possibly exist in this day and age. Still, strange things appear to be going on and the darkness is taking on many forms. Something is out there. Are you safe? (Source: RightStuf)