Well, it starts well enough. Seems to be like a nice story, then suddenly, BAM! Random mage comes out of nowhere and the main character becomes a girl. Okay. But then it does something interesting -- makes it a plot point. The seemingly random event becomes the actual focal point, figuring out who it was, and why it happened.
But that's not why it's awesome. As of this post, the plot is still a kind of fledgling plot, and not really able to get interesting, as there's only five or so chapters. It's the chemistry between the Genderswapped Asuka and the Cross-dressing Yayoi that makes this manga so insanely enjoyable. Between Yayoi's abnormal liking of his new body (which he routinely seems to be ashamed of), to Yayoi's antics, I wound up laughing throughout several chapters.
It is quite a bit ecchi, though, and definitely NSFW at some parts, so if you're gonna read it, be careful as to where you're doing so.
At the time of this post, it's still too early to give it a rating, but I definitely recommend gender bender fans pick this up.