Kazunari Ninomiya
A new Johnny's YouTube channel called ジャにのちゃんねる (Janinochaneru), lead by Arashi's Kazunari Ninomiya, was opened on April 25, 2021. Yamada was revealed as the fourth member to participate, on April 28, in the channel's 4th official video after the 3 ones revealing the silhouette of the 4 Johnny's to be a part of it and the ones where the other members would be introduced.