This is another of the refrains that runs through the Song (Song of Solomon 2:16; Song of Solomon 6:3) expressing the mutual love they have for each other, their commitment to each other, and that they belong to each other. This is one of the themes that gives the Song its unity.
The Hebrew word for desire
here is teshuqah. It is found in only two other places, Genesis 3:16 and Genesis 4:7. In both contexts it is used in a negative way. Here in Song of Solomon 7:10 it is clearly positive and the common idea in all three uses is that it expresses a strong desire, urging, or longing.1 She willingly gives herself to him in his strong desire of her, in the context of their mutual love for each other.2
10 I am my beloved’s, and his desire is for me.