"Black and White" by Niall Horan is a romantic song that tells the story of a couple's deep love and commitment to each other. The singer is reminiscing about the night they first met and how they shared a special connection. The chorus "I see us in black and white, crystal clear on a starlit night" suggests that their love is timeless and will never fade away.

The singer promises to love his partner for the rest of his life, as evidenced by the lyrics "I promise that I'll love you for the rest of my life." He also wants the world to witness their love and commitment to each other when they finally say "I do."

The bridge of the song reveals that the singer cannot promise his partner a perfect life but promises to give back the love he has received from her. The black and white imagery in the song depicts the idea of clearness and purity in their love for one another.

Overall, "Black and White" is a beautiful love song that speaks to the depth and commitment of true love. The singer promises to stand by his partner through thick and thin, regardless of the challenges they may face.