The Guillotine Devil was introduced in Chainsaw Man chapter 158, which came out recently and continued with Fami and Asa's invasion to save Denji. However, the focus this time around wasn't really on them. As security was closing in on them, Fami decided to summon an ally for the battle, the Guillotine Devil, who would be the most recent Devil introduced in the series.
The Guillotine Devil was probably the star of the show in Chainsaw Man chapter 158, particularly because of its strong character design and the way its abilities are executed. While much hasn't been explored thus far, it serves to have a glimpse into Fami's abilities and what her true intentions could be.
Disclaimer: This article contains spoilers for Chainsaw Man chapter 158. Any opinion expressed here belongs to the author and not Sportskeeda.
Chainsaw Man chapter 158 shows the introduction of the Guillotine Devil
Chapter 158 starts where the last one left off and shows Fami and Asa dealing with the guards as the former releases the Guillotine Devil onto them. This creature has the shape of a guillotine, although it has elements of a pigeon and constantly screams part of its name, much to the annoyance of Fami as they are fighting the guards.
Fami also goes on record stating this Devil isn't as strong as it could be because of the contract she made with it, although she doesn't reveal much else to Asa when the latter keeps asking. This has piqued readers' attention since it continues to show that Fami has a lot of cards on her hands and doesn't seem to be really honest with Asa and Yoru. This is something that is bound to play out later.
The Guillotine Devil also showed a few glimpses of its abilities, going as far as cutting a lot of weapons and even the clothes of the guards without much trouble. There is a fan theory already going on that this Devil isn't as strong just because of the deal with Fami but also because people are not as afraid of Guillotines as they once were a few centuries ago, although that is mere speculation.
What could happen in the coming chapters?

Chainsaw Man chapter 158 didn't move the plot forward all that much beyond freeing Kobeni's brother and introducing the character of the Guillotine Devil. This is something that makes the coming chapters all the more important. There are a lot of fans who want Asa to find Denji and finally discover his secret identity. However, knowing Tatsuki Fujimoto's writing style, there is a very good chance that it is going to be swept under the rug.
A major factor that will influence the next few chapters is public safety and its attempts to keep Asa and Fami away from Denji. So, there could be some battles, such as Hirofumi Yoshida stepping in. Most fans were disappointed that Yoshida's battle with Asa wasn't fully shown in the manga, so a rematch could be the best way to go.
Final thoughts
Chainsaw Man chapter 158 saw the introduction of the Guillotine Devil and how it works, which involved it making a deal with Fami that wasn't fully explained in the chapter. It also showed this Devil's ability and how it can cut a lot of weapons and even clothes despite being weakened.
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