I mean, as i said: nuclear levels of cope.
The type of shit that is beyond normal delusion, at the end of the day i think that all he really wants is to make super unpopular teories and if somehow M.I.T.A is reading this thread and choose to make it all canon, he will he here saying "I told you guys months ago", but even he knows that it is almost impossible and Rika judgement day(all her wrong doings and past victims being exposed when her PAST be showed to us) is a matter of time, and if her relationship with shingo mori and iwabuchi (the dude is comparing almost kissing other women than his wife to BLACKMAIL WOMEN into PROSTITUTION) is not enough for he to realize that rika is as dirty and terrible as a person can be, i would like to remember you guys that she described sousuke as a idiot and pathetic looking guy to others (shingo in chapter 1/2, and to iwabuchi recently), the idea of her loving sousuke is ridiculous, that women dont love him in any way, she tolerates him at best, that relationship was doomed to end way before sousuke founding out her secret account.
I think it's fair to say that the relationship between Rika and Sousuke is likely, effectively perfunctory on her part--a means to camouflage her activities from societal judgment by appearing to have the perfect, idyllic family life--bright child, loyal husband, succesful household. She curates the image obsessively, all to divert attention from all her goings-on that earn her huge sums of money doing all manner of unsavory things.
Whether or not Shiho is actually Sousuke's, whether or not the current fetus inside Rika is Sousuke's, almost doesn't matter, though.
This whole way through, we've been party to the Protagonist falling down a dark hole of disillusionment, that his wife doesn't exist--that Rika has never been who she claims to be.
Whether it's sexual infidelity, her criminal actions and enterprise involving blackmail and extortion, coercion and prostitution, cuckolding and voyeuristic filmography, and even the "banal" facets of brand consultation and business advisory work--for sexually deviant/criminal business models, mind--
or the fact she's lied to him about seemingly everything involving herself as a person, Rika Yamada is effectively a ghost, and Sousuke himself a smokescreen for whatever it is Rika Miyase is doing.
And to that end, even if at some point in her past Rika was effectively trafficked (the "whore house" of her familial residence remains a question mark, as far as its history and any involvement she has with her family home being designated as such), it doesn't change the fact that the Rika of today has done
all the things we've seen attributed to her.
You could maybe argue that Sousuke isn't a perfect person--but arguably no one in this series is, save perhaps the two named children in Shiho and Tsubasa. But Rika is the pinwheel to which every other villainous character is connected--everyone that Sousuke runs into trouble with is attached to Rika in some way. The sheer degree of involvement for her to all these shady, exploitative, or downright criminal goings on makes it exceedingly unlikely she's innocently maligned in every accusation against her.
Whether she'll get any sort of comeuppance, remains a question--if it happens, I suspect Sousuke won't be actively involved, for no other reason than his character up to this (potentially endgame) party arc has been remarkably reluctant to enact the sort of harsh punishment & consequences that some readers might be seeking for our main villain.
He had a hand in some aspects of "punishment", but each was tied more to the deepest fear or insecurity of each villain being exposed and brought to the surface--Shinjo's vanity; Shiratori's fear of being cuckolded ('reciprocity' for his victims); Jiu's fear of abandonment by his wife. And in other cases he helped a person--namely Misato most recently, who reconciled her fear of being exposed on the Internet with seeing Sousuke succeed against Iwaguchi.
Each person effectively defeated themselves in some manner, by having a core weakness exposed and then exploited--often tied to the thing they were doing that made them a villain. Which, neat little narrative trick, but we don't see Sousuke taking real agency in doling out justice or even vengeance. More often than not, he rehabilitates those under Rika's control, turning them against her in the end.
And I think that Rika's punishment will be similarly "karmic". It would depend on the truth of her motives in all of this--whether she embodies facets of psychopathy and is chasing an emotional high; or she is a control freak seeking the thrill of risk and danger in doing socially subversive activities and threatening to ruin the lives of whole groups of people; or some other selection of potential modus operandi--Sousuke won't be pulling the trigger, as it were, but the general situation she's in, instead. She'll be hoisted by her own petard, and there's a chance Sousuke is there to pick up the pieces and, like he did with so many other villains in this story, "put Rika back together" and see her changed/reformed (in whatever way that might look).
I think I'd personally rather he be wholly uninvolved, and maybe even see her simply disappear--in that her karma arrives and she gets punished, but it's left unclear what truly happens, and he doesn't know what happens to her, and Rika is simply gone.
He returns home alone, and raises Shiho himself, perhaps with Akiba-sensei making her move at last and they form a new family unit, and Rika is never heard from again.
It would almost feel fitting, in that she sort of embodies facets of the other villains--she covets wealth like Riu; she's obsessed with appearances and identity like Shinjo; she seeks control of others like Shiratori; she is very preoccupied with all things sexual like Misato; she is cunning and conniving and manipulativr like Iwaguchi.
All those things we see in the "midboss fights" Sousuke went through are present in this endgame fight, and so I think any justice that Rika sees will reflect what has happened to the rest of the antagonists. And just as Sousuke had little active role in their defeats (compared to what he could do before and after if he had more agency as a character), he won't be landing the "killing blow" on Rika, but her own games and moves will come back to destroy her.
That at least would feel narratively consistent with what I see the author doing thus far, anyway.
