無垢の領域 - Muku no ryōikiBook - 2016 | Japanese
Akitsu Ryūsei is an ambitious calligrapher who has long left the household finances and the care of his mother to his wife Reiko. Enamored with the calligraphy talent of Hayashibara Junka, he hires her as an assistant for his calligraphy classes, but this connection ends up bringing Reiko closer to Junka's brother.
Publisher: Tōkyō : Shinchōsha, Heisei 28, 
Branch Call Number: Japanese F Sak
Alternative Title: Title also in English : Monotone