Swallow Return

Takenaka Shigeharu could conjure soldiers from beans and horses from grass; Honda Tadakatsu was invulnerable to swords and spears, with a head of bronze and bones of iron. The tengu and the earth spider swaggered about; the Nurarihyon and the nine-tailed fox made a fleeting appearance.
This is a drastically altered version of history. A modern person arrives in the chaotic and supernatural world of Japan's Warring States period, becoming a monk with the Buddhist name "Ryuun".
Then one day, he was suddenly told that he was actually the second son of the Omi Sasaki family, and that his older brother named "Kotaro" had just died. He needed to return to his hometown immediately to inherit the family business, and his first task was to deal with the mysterious "Taimanin".
The story of "The Return of the Swallow" begins here.
P.S.: I originally wanted to call it "I'll Raise Your Wife," "Nothing Tastes Better Than Dumplings," "Life in the Warring States Period," or "From a Straight Man to a Pile Driver," but those were rejected...