サザンオールスターズ
is a Japanese musician, best known for playing the bass guitar for Southern All Stars. As a solo artist, he has played ukulele. He is a fan of Hawaiian music, and is the founder of the annual Ukulele Picnic music festival in Hawaii. For nearly twenty years, Sekiguchi has worked with Akira Sakuma in the "Momotaro Dentetsu" video game series as a music producer.