Chainsaw Man, Season 1 Finale Ending Explained: In the end, we see Aki successfully kill the Ghost Devil with the help of Denji. After that, we see Akana is planning to use the contract that she has with the snake devil; then, she tells the snake to attack Aki, but we see Kobeni is already there to save Aki by stopping that devil snake.
Still, we see that Akana is only trying to destroy Aki, After that, we see Kobeni slowly put knives to her neck and plan to kill Akana instantly. But Aki warns her not to do anything stupid because he wants her detained for further investigation into her plans and more.
The scene now shifts to show Swatari being attacked by devil snakes and dying instantly. Following that, Makima reports that Sawatari had a contract with the Gun Devils to kill and steal Denji’s hearts, which I explained in the post-credit scene, or we will see more in the next season.
Then Makima informs us that, based on reports that Gun Devil took 1.5 kilograms of tissues from the building, we have discovered that there are approximately 5 kilograms of tissues there. After that, Makima tells Denji to kill Gun Devil so that no one will be able to find it, and the scene ends.
This season looks bloody good, which you must check out; however, for those who watched, let me know in the comment box how much you liked it. More information can be found in the Post-Crime Scene Explanation articles.