海原（うなばら） is a poetic word for the wide, open sea, evoking an endless expanse rather than simply a body of water. In the song, the speaker breaks away from a calm, routine life and comes alone into the ocean, making 海原 a memorable symbol of freedom, risk, and starting anew.
Spitz take a love song and make it all about thread. The title, 見知らぬ糸 (threads I've never seen), sets it up: two strangers' lives get tangled, and instead of a mess you end up with something new.
It opens on taste and memory. Something ブルーベリーみたいに甘い (sweet like blueberries) is so vivid it still has flavour 夢でも (even in a dream), and a memory that should wash away under the waves just won't. Then the speaker admits 迷い込んだんだ いつの間にか (I wandered in before I knew it), and asks the other person if they still haven't noticed that fate has already started, even if they feel out of place. I love how casual that sounds. Falling for someone here is less a big moment and more drifting into the wrong room and deciding to stay.
The chorus is the heart of it: the unfamiliar threads 絡まり新しい色に (tangle into a new colour), get 編まれて (knitted together), and become a 薄い衣 (thin garment) that wraps the singer up. Learner tip: 編む means to knit or weave, so the love is literally being stitched into clothing.
The second verse is the bravest part. The singer used to be 飼われた魚のように (like a kept fish), waiting for food in a calm routine, and then jumped out and swam the open sea alone. There's a cheeky line too: ペテンでも構わない (I don't even mind if it's a con). ペテン is an old-fashioned word for a swindle or trick, and saying you'd accept being fooled is a bit much, in the best way. By the end the singer feels 少し強くなれる (I can get a little stronger), which is a very Spitz kind of happy ending: modest, warm, and wrapped in a soft new layer.
Spitz is a Japanese rock band formed in Tokyo in 1987 by four art school students: Masamune Kusano on vocals and guitar, Tetsuya Miwa on lead guitar, Akihiro Tamura on bass and Tatsuo Sakiyama on drums.
They released their first single, "Hibari no Kokoro", in 1991. The single "Robinson" (1995) sold more than 1.6 million copies, "Cherry" (1996) more than a million, and the 1995 album Hachimitsu topped the Oricon chart and won Best Album at the Japan Record Awards.