"Doctor Y" features Kaji who loves to be part of the herd, adores money, uses his skills to get what he wants and is narrow-minded. Last year, when the first spin-off series was shown via the Internet and later shown on TV, it showed how Kaji was sent to a hospital in the countryside and was bewitched and tempted by money when treating his patients but he always managed to achieve his aims in line with the main drama's theme of "never failing". In the second series, he will be at Honokura Hospital which is surrounded by mountains and feels like a place which you would see in horror movies. There is a legend that the hospital is cursed by the spirit of a young girl. From the first night when Kaji reports for work, he goes through a harrowing and comical experience while continuing his stint as a surgeon there.
Takito commented jokingly that he was a bit disappointed that the offer was to appear in "Doctor Y" instead of "Doctor X" but said that he was still motivated and excited after all to be able to participate in this. He also suggested that the story would show the unexpected relationship between Kaji and Kitano and unknown sides in Kitano which had never been featured before.