Does Song of Solomon encourage pre-marital sex?

Someone raised the following argument, claiming that the Bible, in the Song of Solomon, encourages pornography and premarital sex. He had me read some verses from the book, which I've listed below, and told me these verses are the main reason why the Song of Solomon is hardly ever preached in churches today, because of its explicit contents and descriptions. >"Dear brothers, I'm a walled-in virgin still, but my breasts are full— And when my lover sees me, he knows he'll soon be satisfied" (Song of Solomon 8:10). > > "If only you were to me like a brother, who was nursed at my mother's breasts! Then, if I found you outside, I would kiss you, and no one would despise me. I would lead you and bring you to my mother's house she who has taught me. I would give you spiced wine to drink, the nectar of my pomegranates. His left arm is under my head and his right arm embraces me" (Song of Songs 8:1-3). He claims these two verses show that the woman being spoken of was not married. Another example: >"Let him kiss me with the kisses of his mouth-- for your love is more delightful than wine. Pleasing is the fragrance of your perfumes; your name is like perfume poured out. No wonder the maidens love you! Take me away with you let us hurry! Let the king bring me into his chambers. We rejoice and delight in you; we will praise your love more than wine. How right they are to adore you!" (Song of Songs 1:2-4). How should a Christian defend himself against this type of argument? Is there another interpretation of the Song of Solomon which refutes the claim that the Bible is in favor of premarital sex and pornography? If so, what is it? or better still what do these verses really mean?