Dokidoki Onii-chan

One day, a distant relative arrives at our hero's house. Her name is Rumiru. She's a cute girl with big eyes. Our hero met her long ago, but he can't even remember how she looked back then. Rumiru remembers him as a kind boy who played with her when she was little. It seems she has just run away from home after fighting with her mom... Our hero soon receives a phone call from her mother. He tries to persuade Rumiru to go home, but she just won't listen to him. Her mom tells him Rumiru is very persistent. Finally, Rumiru's mom gives up and asks our hero to let Rumiru stay a while... This is how life with Rumiru begins.