Takashi Shiina:
高橋留美子先生、お誕生日おめでとうございます。 原稿は遅れてますすいません。
"Happy Birthday, Rumiko Takahashi!
Sorry, the manuscript is late."
この絵は高橋先生が描き下ろしたイラストを、構図そのままで本編のカラーページにするという企画で描いたものです。たしかもう一枚、同じことをやった気がする。
"This picture was drawn by Takahashi-sensei as part of a project to make a color page of the book with the same composition as the original illustration. I think I did another one of the same thing."
Note: He's talking about the Sesshoumaru and Rin Art, that was also drawn by Rumiko Takahashi
Source: https://twitter.com/Takashi_Shiina/status/1711677512189980740