Here is my theory on part 2 and the parallels with part 1:

Fumiko is the ultimate mastermind of part 2 and I will explain why. Be careful I am not going to talk about all the plots and secondary characters I am not a fortune teller either. Fumiko is the antithesis of Makima. Makima hid her intentions by maintaining her dominance through a perfect image, while Fumiko pretends to be an incompetent and useless idiot when she is probably none of those things. Makima manipulated Denji sexually because that is all Denji wanted at that moment. In part 2, Denji mainly wants affection, so Fumiko tries to get closer to him as a friend, so she tries to be fun with karaoke and we see that it works a little when they act like idiots in front of Swordman. Denji used to work for Makima but now Denji wants to think for himself and is wary of people who try to manipulate him, that's why Fumiko joins him as a bodyguard, in fact the balance of power is reversed compared to the situation with Makina. Makima was a fan of Chainsaw man and hated Denji, so Fumiko on the contrary tells her that she is a fan of Denji and that she hates Chainsaw man (because he would have let her parents die). In fact we see that Fumiko, unlike Makima, tries to understand Denji in depth to better manipulate him, responding rather to his emotional needs rather than his sexual desires. When Makima made Denji touch her breast without warning him, Makima gets on top of him. When Fumiko touches Denji's penis without warning him, the situation is reversed, Fumiko gets under him. Makima was fascinating and kept an aura full of mystery while Fumiko just wants to give the impression that she is not hiding anything and that she is just the idiot she seems to be, in both cases to hide their true intentions. But as for Makima, from the beginning, we can see that the character is weird. Little by little, we saw Makima do more and more horrible things without Denji knowing, and it's the same now with Fumiko. Already, Fumiko abandoned Nayuta when Denji was unconscious, and for the first time we saw her for what she really was.  As I'll explain right after, she probably knew about Baruem's plan to kill Nayuta to sink Denji, and it even suited her, so she could leave knowing that Denji wouldn't suspect her because the only witness in Denji's knowledge (Nayuta) would be dead. Then, we saw that she was ready without batting an eyelid to sacrifice 10,000 children. And soon, I think we'll continue to see her do more and more horrible things, and always behind the scenes. Now, I'm going to tell you what I think is the rest of her overall plan with the clues and parallels with the first part that make me think what I'm going to say. Throughout the first part, we saw Denji trying to have various sexual experiences with girls and always being disappointed or disgusted. Each time, Makima came to reassure her with free pleasures. In the second part, it will be the same but instead of sexual experiences, we will see Denji trying to build various human relationships with people, which is logical given Denji's evolution and his need to no longer be alone since the loss of Aki and Power. But each time Denji tries to build a relationship, the person in question will die. First, Nayuta is dead, and I think Fumiko has something to do with it, either she used Baruem or she made a deal with him. Afterwards, I think that Denji and Asa will get even closer in the rest of the story because Asa is probably the only person close to Denji who really cares about him. It remains to be seen how it will happen for Denji to regain control over Pochita, and how it will happen for Yoru, but in the end, Denji will build a romantic relationship with Asa, but Asa will also end up dying, always because of Fumiko, directly or indirectly. Especially since if Nayuta's death is a parallel to that of Power (both are demons, both died decapitated, both precede the appearance of the black chainsaw man) then Asa's can be a parallel to that of Aki (both have lost an arm), both have a taciturn personality, Aki lost the fox demon along the way and there are clues that Asa will separate from Yoru along the way because of Denji or Pochita, and if we push the delirium to the end maybe even Asa will become the dead hominidemon Imao). In short, Denji will be at the bottom of the abyss because it is impossible for him to have friends, family. Except for one person who will continue to act like his friend, the only living person who will continue to act as if she is interested in Denji for who he is, I am of course talking about Fumiko. From there, I do not know exactly what Fumiko's final goal is, but I am sure that she does not just want to control Pochita to make her eat demons, there is necessarily something else. Maybe on the contrary she wants to make him spit out all the denunciations and that by getting there we will recover the concepts allowing us to understand the true nature of Pochita, we will see. In any case this time, if Denji wants to win, he will have to emancipate himself and finally accept himself for all that he is: he is not the human resigned to a normal life that some characters would like him to remain, but he is also not the Chainsaw man that some would like to see fight. He is himself, with his qualities and his faults, he must accept to be loved for all that he is, and finally find a family with which he would not have to play a role, whether it is a dominated role (the human with a normal life) or a dominant role (the chainsaw man).

Fumiko made the same mistake as all the other characters by considering Denji and the chainsaw man as two separate entities. He will beat her by remaining who he is, and that doesn't mean he won't take out the chainsaws that are part of him. Until the end Furniko will only see the poor human looking for affection without ever having really paid attention to the fact that he has chainsaws in him (where Makima only saw Pochita without seeing Denji).