One idea could be a rengoku fanfic where he trains a new group of young slayers. It could focus on his unique teaching methods and how he instills his values in them.
Tanjiro would be a great character to pair with rengoku. Their different personalities could create an interesting interaction. Tanjiro's kind - hearted nature and rengoku's fiery determination could lead to some great storylines.
This hymn is often associated with the celebration of the Epiphany. It reflects on the journey of the wise men in the old story. The words 'as with gladness' set a positive and joyous tone, much like how the wise men were filled with joy when they found the baby Jesus. It's a hymn that helps to bring the story of the Epiphany to life in a musical and lyrical way.
One of the main themes is adventure. Since rengoku is often involved in battles and dangerous situations, the fanfics may take the reader along on these adventures. They might face demons together and their relationship develops through these shared experiences. Also, loyalty is a big theme. Rengoku is a very loyal character, and this loyalty extends to his relationship with the reader in the fanfics.
Weekend Parents was a TV series that told the story of Yu Zhiyuan and Zhao Jiani, a couple who worked hard to participate in their son's growth. They had been married for five years. Their son, Yu Zhenxuan, usually lived at his grandmother's house. He could only bring the child home on weekends to enjoy a short period of parent-child time. In the process of struggling, Yu Zhiyuan grew from a reporter to an editor-in-chief, and Zhao Jiani also rose from a small woman to an employee of a foreign company. They faced the temptations of society and kept their bottom line time and time again, advancing toward their goals. In the end, they stuck to the values of the times and never left each other. They understood that companionship was the deepest love for children. The drama was starred by Liu Kaiwei, Wang Ou, Zhang Meng, Zhu Yongteng, etc. It was an urban family drama with the theme of parent-child relationship.