This entry to the series feels like it would be the beginning of season 2 if it was ever animated.
Knuckleduster's goal of saving his daughter in the previous volume was achieved, so he basically hangs up his gloves so to speak, leaving Koichi without guidance. In this volume, Koichi has to stand on his own two feet and make his own decisions without automatically defecting to his master. Knuckleduster was a push into the vigilante lifestyle, but now Koichi has to choose where to go from now on on his own.
This volume was a little slower after the previous volume's climax between Knuckleduster and the villain possessing his daughter, Tamao, but it begins to set things up for an even tougher challenge for our main cast. The villains are a hell of a lot tougher now. They're not just temporary villains; they become permanently changed after taking copious amounts of the drug Trigger, and are significantly more dangerous. There's also talk of a mysterious organisation behind it all that makes you wonder what their goal is.
We get to see more pro-heroes in this story, in particular Midnight and Eraser. We get to see their friendship dynamic and see them outside of hero work. Midnight is surprisingly very motherly for someone who has a very provocative hero costume and who would fit right in at a BDSM party. Eraser Head, or Mr Aizawa as most know him from the main series, is one of my favourite characters in this universe, so it was great to see more of him in this. We see how he works as a pro-hero, and his relaxed approach is very similar to how he teaches at U.A. He's laid back and a hardcore introvert, which is a couple of the many reasons why I love him. Another pro-hero we see more of is Fat Gum, which was really cool as he was an intriguing character in season 4 of My Hero Academia.
The main duo's (down from a trio since Knuckleduster has seemingly left the scene - for now at least) friendship is so adorable. It's wonderful to see them grow together. Koichi and Pop Step are like brother and sister and it's so sweet to see Koichi look after her like an older brother, and Pop Step looks up to him like a younger sister. I also enjoyed Pop's developing friendship with Makoto, someone she was previously jealous of, now turned a good friend.
Speaking of Koichi, he grows even more in this volume. His quirk's usage expands again, and it becomes more and more useful as time goes on. He unlocks new abilities. You can see how if he were a student at U.A., his quirk would have expanded more and more, and it's more heroic than originally thought to be.
As mentioned previously, this volume felt slower than the previous one, but that's expected. It was a sort of comedown from the previous plotline, until around 50% of the way through, when it picks up again with an epic fight scene against a villain, where Koichi gets to help the pro-heroes again. The villains are getting scarier, the danger increasing, and things are changing. It feels like Koichi is about to begin a new phase of his vigilante career now his master has left, and that's very exciting to see. It's also great to see pro-heroes and familiar faces from the main series who didn't get as much screen time pop up time and again.
I'm looking forward to volume 6!