Hand to God, really. It was probably one of the most visually unique programs I'd found in recent memory, and its commitment to the visual theme of a circus reminded me of Soul Eater's gothic design motifs in a refreshingly good way.
But having finished its (insofar) only season, I feel exhausted, and yet, content-wise, I feel grossly underfed.
At first, what may appeal to you and make you want to watch the show is the art. After all, it's very colorful, bright, and overall beautiful. It's enticing to say the least, and the first thing that hits you is probably how beautifully animated and drawn it is.
After the outstanding art settles in, the characters and plot may seem lacking. It centers around Nai and Gareki; a dynamic duo who met by chance and chance alone. They're soon intertwined into a world of action and danger via Circus, a protection agency whose sole mission is to protect the world from the Varuga and Kafta. (You'll find out more about them throughout the show.) The two soon begin building friendships with some of Circus's members, such as with Yogi and Tsukumo. The show itself is very well paced for such a small amount of episodes. However, the show itself ended leaving a lot to be asked for and desired. Many questions were left unanswered, and that usually doesn't leave a good taste in your mouth, particularly with no promises of a future season.