Zenzo Saeki

As the father of Koshiro and Nanoka, this architect is a man in his later middle years who struggles with anxious worry and a degree of obliviousness. Despite his flaws, he deeply cares for his children, showing a distinct favoritism towards Nanoka. He strives to make her feel comfortable in her new environment, though his past infidelity with Makie is implied to be a contributing factor to their separation.