As the special itself calls it, this is episode 25 of the show. A better name would have probably have been: Kill la Kill Epilogue.
After all the chaos of the main story, our protagonists have to finally graduate from Honnouji Academy, and this graduation is both literal and metaphorical. The theme of the episode is about graduating as in, moving forward with life. Moving forward while remembering the past and using what happened as lessons to bettering oneself. About how graduating from the uniforms that we had to wear is normal and has to happen.
The Art/Animation/VA/Direction is all the same as the main show, so I won't bore you with stuff you know.
This episode puts the cherry on top of the amazing cake that Kill la Kill was, if you loved the cake, you should really make sure to finish all of it.
I'll keep this short. I watched all of Kill La Kill, and had to drag myself through bits of it. This short didn't give me the same issue, and honestly the main reason for that is it didn't have as much fan service.
The characters were mostly clothed, and the story as a continuation of the original series worked well.
It was short and sweet, and I had to smile at points because the characters had finally, finally, shown signs of development.
Enjoyed this a lot more than the original series but, unfortunately, it's impossible to watch without watching Kill La Kill.