The story starts with a Third-year junior-high school student named Keita Suminoe. He is living in a residence with his older twin stepsisters, Ako and Riko, who flash, kiss, and display their love for him in public.
KissXSis Cosplayer last AFA X
Keita begins to become charmingly attracted to his two stepsisters and he initially dislikes himself for it, although they share no blood-relation to him. Seeing this attraction, his two parents inspire him to get married to one of them, with Ako and Riko persistently at chances to try and get Keita's attention, or working together to carry on his attention away from other girls.
Our Steady Boy by Yui Kaori (Yui Ogura and Kaori Ishihara)
Cosplay MTV of Kiss X Sis