Katsute Mahou Shoujo to Aku wa Tekitai Shite Ita.

She's a magical girl, sworn to fight for peace, love, and justice. He's a lieutenant, born into a military family that serves an evil empire. And yet, it was love at first sight...From Inu x Boku S.S. creator Cocoa Fujiwara comes a four-panel comic about hostile enemies who won't kill (and love) each other!
(Source: Yen Press)
Notes:
- Includes 1 extra chapter and the one-shot "Beauty and the Beast", which is included with the third volume of the manga.
- The manga was cancelled due to the mangaka passing away.