This is a right-leaning decrease that reduces the number of stitches on your needle by 1.
The purl 2 together is identical to the knit 2 together, only it’s used on the purl side (usually the WS) of the fabric. Doing a p2tog on the purl side will result in a k2tog on the knit side.
- With yarn in front, insert your right-hand needle from back to front through the first two stitches on your left needle.
- Purl the two stitches together as if they were one.
If you turn your work around, you’ll see a k2tog on the other side.