Some time ago, the asteroid Kumaria exploded in the depths of space.
The resulting fragments became a meteor shower that rained down on Earth, and for some reason, bears all over the world rose up and attacked humanity! In "Man vs. Bear," the bears ate the humans and the humans shot the bears, resulting in a seemingly unending battle and a cycle of hatred. In the end, a giant "Wall of Extinction" was erected between the humans and bears and a state of mutual nonaggression came to pass...
The human world.
One morning, Arashigaoka Academy students Kureha Tsubaki and Sumika Izumino were by themselves and saw the "Yuri Flower" that bloomed in a flower bed. The two are friends as well as lovers. The flower bed is an important place to the two. At that moment, the Bear Alarms ring out! The bears are invading the human world, and humans are being attacked! Are they really those bears? One mystery invokes yet another mystery, one after another...
NOTE: May contain spoilers. I'm discussing how the story develops thematically (which will likely give away some plot elements).
Wow, a 7, huh? Way to take a stand, me.
First off, I haven't seen the anime yet. I gather (from reading its reviews, and from author commentary in the manga) that they go in a rather different direction. This work does not seem to be using the whole "bears" thing as a metaphor for systemic social differences (i.e. being gay).
Instead what you get in this series is a meditation on the nature of reality, and how a combination of upbringing and experiences can turn one's perception of
reality completely on its head. And a study of how love sometimes can--and sometimes can't--bridge the gaps between one person's reality and another's; and what it means to inherit expectations, to deal with childhood trauma, and to live with soul-crushing guilt.
This is potentially really good stuff; and the fact that it's set against a backdrop of magical space bears makes it even better. Yay weird! Unfortunately, it reads like one too many head-fakes. Are the bears real? Does one person have a special insight into a hidden world, or is that person just delusional? Are metaphors intergenerational? (What about yuri ships?)
Part of this is an intentional effort to make the narrative ground constantly shift under the reader's feet. There's many layers of symbolism happening, and this is an interesting thing; unfortunately it jumps around just a little too much, enabling the uncharitable reading of a creator being indecisive or intentionally obtuse rather than making a carefully thought out thematic point. Don't get me wrong, it's not like you need to read it three times to understand what's happening; it just straddles the line between revelations that make you go "ahhhhh!" and ones that make you feel like you're suffering narrative whiplash.
I also--despite, c'mon, it's in the title--felt like the yuri angle was kind of forced. The love triangle is resolved way too easily; there's not any real motivation or story-evidence for the blossoming of romantic feelings among most of the characters; and anyway soon enough we're going to be more interested in sorting out what's going on in the world and in her mind than what's in her heart. Still, given the central thematic role that "true love" and "fated persons" play in this story, I could stand to see a little more evidence of actual love. (And don't start with me by saying that the manga is intentionally embracing yuri-romance cliches; that might be true and it might not, but that's not an explanation, just an excuse.)
Finally, I felt that the complicated backstory and character history just got out of control. There's drama, there's fate, there's karmic connections or whatever; then there's just too much.
So, ultimately, a seven: when a manga is trying (just that bit too hard) to do interesting things, and is carrying too much baggage from thinking about just how clever and deep it is.