wool - n - gather

Purl 2 stitches together through back loops is a right leaning single stitch decrease on the purl side. It a little bulky which can be used as a design feature.

To make this stitch, insert the right hand needle into the stitch after the working stitch through the back loop then insert it into the working stitch through the back loop, wrap the yarn around the right hand needle and draw it through both stitches, slip the worked stitches off the left hand needle leaving the new stitch on the right hand needle.