What do these two sentences mean?
1.you're one in a melon
2.I'm bananas for you

I saw these two in a samll story and I feel strange. Are they exist?

Question

What do these two sentences mean?
1.you're one in a melon     
2.I'm bananas for you

I saw these two in a samll story and I feel strange. Are they exist?

Answer

1. It should say you're one in a MILLION, not melon.
2. "Bananas" is another term for crazy. As in, "I'm crazy for you."

Answer

1. One in a melon is a play on words because the word "melon" is similar in sound to the word million. 
2. Bananas is a way of saying crazy. So, the sentence means "I am crazy for you."