Why is there a photoshop tag for this?

I did. All I saw was a crop. As far as I can tell, no real editing was done beyond that. That doesn't warrant a photoshop tag, as far as I know.

Cropping is not photoshop specific, as for what the tag means. I did use photoshop to crop it, but otherwise it's unedited.

Photoshop is just a generic term to mean edited. If it's just a simple crop with no edits, it's unneeded.

woha kisumi once again a brilliant job

This one isn't even a Kisumification. It's an original artwork by an artist generous enough to do it for me. If you check the source link, it's Kisumi with Scy, SciFi's RP genderbend. (Not Sci's fault or choice by the way... I was bored and had a weird potion.)