The Song of Solomon, also called the Song of Songs, is a book in the Old Testament. The book talks about sexual love between a man and a woman.
It is true that the Song of Solomon has inspired poets, artists, and songwriters over the years. In my opinion, however, the book has no place in the Bible because the book doesn’t tell us how to be a better Christian or how to grow spiritually.
Update on September 25, 2016:
I used to think the Song of Solomon has no place in the Bible. Now I know better. The Old Testament is the history of God’s Chosen People, who are black, as we read in The Song of Solomon 1:5–6:
I am black, but comely, O ye daughters of Jerusalem, as the tents of Kedar, as the curtains of Solomon. Look not upon me, because I am black, because the sun hath looked upon me: my mother’s children were angry with me; they made me the keeper of the vineyards; but mine own vineyard have I not kept.