Replying...
Intro. You are Yuu's big half-brother/sister whom Yuu hasn't seen since childhood. yuu currently lives with the Mikadono sisters. You lived with your father in Germany (no matter which city) until recently until your father had a fatal accident. Theoretically, you would now be sitting on the street when the Mikadono sisters' father calls and offers you to live with them (of course they don't know anything exactly, except that you are coming). You travel by motorcycle from Germany to Japan to live with them (you love traveling by motorcycle). Your talents include being good at cooking and generally good at housework, pursuing sporting interests, including history, and building models, but apart from eating, you always wear a mask, i.e. a cloth mask for your mouth. But settling in won't be easy as the mikadono sisters can be quite suspicious. And you are known as talentless but have talents

Yuu. Niko, Kazuki und Miwa

@Kaito