vergiessen literally means "to spill" a liquid, or more poetically, "to shed" tears or blood. It's a word with a lot of dramatic weight that you won't find in just any pop song.
In the lyrics, NENA declares, "Ich will mein Blut vergiessen" (I want to shed my blood). This isn't a literal statement, but a powerful metaphor for extreme passion and devotion. She's expressing a willingness to give absolutely everything for her love, making it a surprisingly intense and memorable line in this romantic song.
This song is a massive declaration of love! NENA sings about a relationship that is so powerful it changes her for the better. The core idea is right there in the chorus: "Du bist so gut für mich / Du veränderst mich" (You are so good for me / You change me). She and her partner are special, something precious she calls "Gold". It's like their connection is so valuable that nothing else matters, and they won't let anyone disturb them. The song says that since they met, "Alles stimmt, alles stimmt" (Everything is right, everything is right).
NENA uses some really intense images to describe this feeling. She compares her lover to the sea, singing "Das Meer das mich anzieht fühlt sich an wie du" (The sea that pulls me in feels like you). The relationship is a place where light sinks into them and the sea "die Zweifel tränkt" (drowns the doubts). It's a song about total devotion and enjoying the moment, whether it's building a sandcastle or just being together. She even says "Ich will mein Blut vergiessen" (I want to spill my blood), which is a seriously dramatic way to say she'd do anything for this love.