Takaho was pleasantly surprised when it was announced that her older cousin, Fujistsugu, would be moving in with them. He was her first crush and she was hoping to deepen her bond with him as a little sister. Little did she know that her seemingly handsome and perfect cousin was actually—

Most people would freak out if their new apartment was haunted. But Gotou Seiichi actually welcomes the supernatural, as long as it's a cute ghost like Uehara Hinako. Seiichi comes from a family who has spiritual awareness and willingly chose the apartment after he heard rumors of a female ghost haunting the place. He instantly falls in love with Hinako who tries every trick she knows of scaring him out. But with every attempt, she makes him fall in love with her even more.

(Source: MangaHelpers)

From MangaHelpers:

Every 666 years, the ruler of the demon world changes. All the children of the former ruler must battle to see who will ascend the throne. To do this, these 'Satans' will team up with the human sorcerer 'Solomons' and fight in pairs. The Solomon of the winning pair is granted one wish.

This 4-koma follows the story of one of those Satans, called Aini. Unfortunately, the human who summons Aini is actually just an erotic doujinshi writer who was doodling. He seems really into Aini, and he makes it clear his wish is going to be something (probably perverted) involving her. Their first battle is against another doujinshi writer, a girl who's really into tentacle porn. Since none of the Solomons have any skill with magic, they're going to have to find a different way to battle it out... [tethysdust]