A School Song Is Hidden Inside: Ryusei Sakuma and OZworld Revisit Their Hometown on "Those Days"

Most artists sample old records. Ryusei Sakuma and OZworld sampled their school song.
You probably won't even notice the elementary school anthem hidden inside "Those days -童神～天の子守唄～- feat. OZworld", but for the R&B singer Ryusei Sakuma and rapper OZworld, it's one of many details that make the song their most personal collaboration yet.

Written about the Okinawan town of Kadena where they grew up together, the track is packed with childhood memories only they could tell. The lyrics reference local landmarks, the period when Ryusei Sakuma transferred schools, and even a phrase borrowed from the elementary school anthem they once sang together.

While rooted in specific memories, "Those Days" reaches beyond nostalgia. The song carries a promise to remain true to the feelings that first inspired them, while expressing a hope that the two can one day return home stronger after forging their own paths beyond Okinawa. Rather than simply looking back, it reflects on how the places we come from continue to shape us long after we've left them.

Adding another layer of meaning, the track samples "Child God (Heavenly Lullaby) [童神 (天の子守唄)]" by fellow Kadena-born singer Misako Koja. A song generations of local children have grown up hearing, its inclusion connects the artists' personal memories to a wider shared cultural experience. Producer Seann Bowe reimagines the beloved melody through a contemporary Island R&B and neo-soul lens, preserving its warmth while introducing a fresh, modern groove.

Together, Ryusei Sakuma's soulful vocals and OZworld's reflective verses transform "Those Days" into more than a song about the past. Built from hometown memories, lifelong friendship and a melody generations of Kadena residents know by heart, the song turns a deeply personal story into one that resonates far beyond Okinawa.

As Ryusei Sakuma continues carving out his own lane within the emerging Island R&B scene, "Those Days" stands as one of his most personal releases to date, offering listeners a rare glimpse into the people, places and memories that shaped both artists long before music brought them to wider audiences.