2-stitch decrease slanting left, involving 3 stitches; slip the first st purl-wise with its yo, go behind the second stitch and put the right-hand needle into the third stitch purlwise. Hold the second stitch to the front as you slip the third stitch to the right-hand needle. Place the second stitch onto the left-hand needle and purl it, then pass the third stitch over, then pass the first stitch over with its yo.
(Sorry for the video quality. Thank you!)
