Anetachi ga Zenin Juudo no Brocon datta

Serialisation of the original work uploaded to Syosetu. I got myself three sisters in law through my dad's second marriage. The youngest sister: Natsuki - 17 years old - A third year in high school. The second oldest: Akina - 23 years old - A university associate professor. The oldest one: Touka - A 27 year old working adult. They all have different hobbies and personalities and the only thing they have in common is ―――― that they all are severe brocons?!? (Source: Kadokawa Sneaker Bunko)