Yorinuki TSF no F no Hon

Jealous of his older brother's grades and constant pestering, Ryouji has a chance encounter with a mysterious woman who grants him a necklace that'll "steal that away from him." Upon wearing his new gift, his body changes into a beautiful, busty succubus! Now he has the power to take more than just his brother's talents! (Source: Fakku)

1. Chapter 1 Since turning from a scholarly older brother to a petite younger sister, "Lili" is trying to adjust to her new life as a succubus with little success. While her body becomes more feminine, the more she loses her original self, and she's gotta do something! What's not helping is that her new big sister says the only way for her to obtain her old abilities is to feed as a succubus. With not much else of a choice, Lili might as well give this a shot! 2. Chapter 2 In order to make up for her lack of studying, Lili is using her summer break to attend a cram school, but her grades aren't improving at all. Even with the help of her class's top student, Daisuki, typical studying techniques are failing at every corner. If she can't gain knowledge through usual means, maybe it'll take a succubus’s touch to steal Daisuki's! (Source: Fakku)

Katsuya just got something special that Hiroyuki cannot believe! Katsuya shows off a magical ring, and when he slips in on, his body takes on the shape of his most ideal girl. Amazed by the transformation, Hiroyuki puts the ring on and feels his body transforming, but as he continues changing, his mind is also forgetting his former self. Now they have fallen into Katsuya's trap… (Source: Fakku!)