Based on the lyrics, it seems that the song is about the bitter consequences of a failed relationship. The song uses "sour" as a metaphor for the singer's relationship with their ex-partner. The singer thought their partner would be sweet (like candy), but instead, they "spit out" the singer, leading to a sour taste in the singer's mouth.

The lyrics suggest that the singer was deeply invested in the relationship and saw their partner as someone who completed them ("Calling you my crown"). When the relationship ended, the singer had difficulty coming to terms with it ("My heart is so sour without you").

The chorus repeats the idea that the singer's heart is sour without their ex-partner. They struggle to move on and are haunted by the bitterness of the breakup. The second verse suggests that the singer experiences the pain of separation in a very physical way ("When the tears touch my mouth / I taste the bitterness like you").

Overall, the song portrays the pain of a failed relationship and the struggle to let go of someone who was once a significant part of the singer's life.

Sour candy in your mouth
Thought I was sweet
But then you spit me out

I was so down
To call you my crown
Then you fell out and now

I'll never know how sweet you taste
I let you go and slip away
I know it hurts but it's the truth
My heart's so sour without you

My heart's so sour without you
My heart's so sour without you
My heart's so sour without you
My heart's so sour without you

When the teardrops touch my mouth
I taste the bitterness like you
Got me speechless and it stung my tongue
I'll never get over you
Every day I'll wonder what you're like
When you touch my lips

I'll never know how sweet you taste
I let you go and slip away
I know it hurts but it's the truth
My heart's so sour without you

My heart's so sour without you
My heart's so sour without you
My heart's so sour without you
My heart's so sour without you

I'll never know how sweet you taste
I let you go and slip away
I know it hurts but it's the truth
My heart's so sour without you