semelparous is a yuri manga written and illustrated by Jun Ogino, which focuses on soldiers known as the Bulwarks defending our world from monsters called kaiju.
Seven Seas Entertainment licensed the manga for English release. This first volume contains chapters one through to four.

Front cover of the first volume of semelparous, featuring Yorino Aratsugi and Youko Kaminoi
Yuri Love is a Battlefield
Ever since they were young girls, best friends Yorino and Haruka have been training to join the ranks of the Bulwarks – soldiers who defend humanity from the kaiju trying to break through. But when Haruka is killed during a routine drill, Yorino’s world is shattered. Will she ever be able to open her heart to another? Strap in for intense, apocalyptic romance!
semelparous starts by introducing us to Yorino, and Haruka – one of which is not fated to be sticking around for too long, as the blurb gives away. It details their time spent training to join the Bulwarks, right up until the fateful incident that tragically takes Haruka away from Yorino.
It is from there where the story proper starts, with Yorino officially becoming a Bulwark. She partners up with Youko Kaminoi, and discovers more about how Bulwarks empower each other, as well as the secrets of the kaiju.
As already stated, the Bulwarks fight kaiju. Humanity fighting giant monsters sounds very Attack on Titan, and yeah, semelparous definitely has elements of that. However, semelparous definitely handles its yuri a lot better than Attack on Titan could ever hope to – which you would hope, considering this is advertised as a yuri story.
Of course the romance is between the two lead characters – Yorino and Youko. I didn’t really feel like the pair clicked at first, but as Yorino discovered more about Youko, things really started falling into place. Yorino also being more willing to reciprocate Youko’s advances certainly helped with that, too.
Towards the beginning, it does feel like Yorino could become the type of character who is obsessed with nothing but revenge. However, she is provided with an opportunity to have a somewhat normal life, which leads her to reconsider things somewhat. I quite liked that bit of character development; definitely much better than having Yorino push everyone away from her.
I like Youko’s character quite a bit, too. I didn’t expect her to be so forward, but it turns out that’s exactly the way she is. Her personal reasons for fighting the kaiju also come to light towards the end of this volume, and that’s something that certainly captured my interest. Yorino’s as well, now I think about it…
I really liked this first volume of semelparous. Whilst the whole theme of humans fighting giant monsters is a very familiar one, the characters drew me in. As too did the way in which the world works, particularly when it comes to how Bulwarks use their powers. A strong start for this serious, I am very eager to see where Jun Ogino takes it from here.