Boku wa Imouto ni Koi Wo Suru Volume 8 (Manga) Review

Plot: Are Yori and Iku really related? Can they mash their groins together without people going ‘ew’?

Also, terrible things, but that’s to be expected.

Breakdown: When we last left Iku, she was about to be gang raped under orders of Tomoka.

The manga is just full of fun times.

Yori is distracted by Ogura, but the jig is up when he mentions Tomoka’s name. Yori manages to make it to his dorm room before anything can actually happen, and he beats up the three freshmen who were trying to rape Iku.

While the boys are getting their own vague punishments, Yori’s punishment for having a girl in his room again and assaulting the boys is expulsion – an outcome no one saw coming, and to which everyone has their own reactions.

Tomoka is in shock because she always intended on using the threat of expulsion as a trump card in keeping Yori to herself.

Yori is devastated because he knows he can’t return to their old house without ousting his and Iku’s relationship.

Iku is….


Now, I was going to give her a pass on feeling this way because she herself admits that it’s selfish and insensitive to cheer that he got expelled……But…..


….Then….she THANKS…..Tomoka……..for doing that to her since it resulted in Yori being expelled……

Fuck….this…..stupid…..dependent…….putrid sack of garbage.

They frame it like Iku thought this was Tomoka’s grand master plan all along (And she just didn’t think to tell Iku about it so she wouldn’t be forever traumatized by the near gang rape?) and that’s actually what she’s thanking Tomoka for, but fuck that, no.


That is too stupid for words. Especially since Tomoka explicitly told her to not yell for Yori when it was happening, and such a plan, in a just world, would have resulted in all of them getting expelled – hell, some of the boys might have seen legal action. Iku may be so dumb I’ve believed several times that her brain was replaced with a toaster at some point in her life, but I refuse to believe she’s that dumb canonically. If she is, she wins the award for dumbest manga character of all time. She is frustrating on a whole new level, it’s amazing.

You know what happened after that?

Tomoka slapped her and said Iku’s so stupid that it’s annoying.

….And I cheered.

Legit, audible, cheers.

Do it again! Do it again!

I should not be cheering on an evil soulless bitch of a girl after she just orchestrated a gang rape on someone because she slapped the intended victim and called her stupid and annoying. I am simply in awe at the things this ridiculous story continues to make me do. I am floored.

Moving on….*more sighs* Iku is coddled by both Yano and Yori after the fact, and Tomoka decides to give one last jab to them by teasing that she intends on telling their mother that they’re in an incestuous relationship. Yori calls her on her bluff, but DUN DUN DUN, their mother is in the doorway and, of course, she heard what Tomoka said about the incest and asks about it.

In the next chapter, Yano makes a valiant effort to cover up what was said by confirming that he and Iku are dating. Iku shakily says she loves Yano in order to maintain the charade, but Yori is all too aware that his mother is now nearly entirely convinced that they’re in love with each other – she’s just holding onto the slight bit of denial that such a thing could be happening.

His mom is unable to reverse the decision to expel him, so Yori heads back home. That night, Iku says she wants to kiss Yori, but Yori, realizing their mother could be listening, yells at her to stop being so noisy and let him go to sleep. Good call, because their mother was indeed starting to listen at the door.

In a text message, he apologizes to her for snapping, explains why he did it and gets a kiss from her anyway.

The next chapter is kinda boring, but also stupid because this manga is talented like that.

Yori and Iku get their new summer uniforms so they’re getting all hot and bothered in their room because apparently their super suspicious mother finds it to be perfectly fine to both let them still inhabit and dress in the same bedroom.

The two of them are trying to keep their relationship a secret from their mother and everyone else….and they suck at it.

First, they start to nearly make out in their unlocked bedroom and, of course, their mother bursts in and nearly catches them. Yano shows up to offer some ‘I’m Iku’s boyfriend’ cover up, but Iku is actually nervous to get on his damn bike in front of Yori just because Yano’s telling her to ride on the ‘girlfriend seat.’ Being fair, I think in motorcycle terms, that’s called the bitch seat. And I believe in this manga terms, that’s called the Tomoka seat.

Yori decides to ride with Yano and leave Iku behind. Way to act more suspicious, Yori.

At school, he staves off thirsty girls by saying he has a girlfriend. Then Iku can’t help herself but dive into Yori’s arms when she arrives at school. Of course, people instantly assume that she’s the aforementioned girlfriend (Mori, the daughter of Yori’s real dad – Oh oops, spoilers whatever – also brought up that Yano has mentioned Iku having a boyfriend) Yori denies this by saying they’re twin siblings, which surprises everyone.

This is merely the second time in eight volumes that people have mentioned Yori and Iku don’t look like twins. This is also the first time people seem to be surprised that they’re fraternal twins – not identical, which is silly because everyone knows it’s impossible to have opposite gender identical twins. Merely the fact that they’re opposite gender already makes them not identical.

They go even further by saying Iku and Yori look nothing alike, which also makes no sense. Fraternal twins look just as similar as any other sibling, and Iku and Yori look about as similar as any other pair of siblings. The manga has deeper physical differences (Eye color/hair color/eye shape) but in the anime they look extremely similar.

This being said, Mori points out that she looks more like Yori’s sibling than Iku does.

This does make sense because they share the same father and their character designs look more similar, but is that implying that the father’s genes are the ones that matters most in terms of physical appearance? Iku and Yori are half-siblings made twins through heteropaternal superfecundation. They share the same mother and shared the same womb, but don’t have the same father.

Yori and Mori have the same father, but not the same mother. I’m definitely not a geneticist, and physical appearance can vary widely, but it’s like the manga is saying that, because Yori and Mori have the same father they, by default, look more related than Iku and Yori when, logically, they share just as many genes. They’re both half-siblings to Yori yet the manga is acting like Mori is the ‘proper’ twin sister.

Gene distribution between siblings does rely heavily on dominant and recessive genes, so perhaps Yori and Mori’s father has more dominant genes than Yori and Iku’s mother does, or the ones the father has create more obvious differences than their mother’s.

Again, I’m no expert on the topic, far from it – in fact I’m researching as I go – but it does seem weird that they’re making off like Iku and Yori aren’t related at all while Mori is hinted at being the ‘truer’ sibling when they, technically, have the same genetic relationship to him.

Moving on, Mori goes to her father, Yuugo, and talks about Yori being at their school. He decides to give a surprise phone call to Yori and Iku’s mother and talk…about Yori. Dun dun dunnnnn.

Next chapter, after some pointless PE stuff and Mori calling Iku ‘chubby’ and telling her to go on a diet, because no one can ever be likable in this manga ever, Yori and Iku’s family have dinner with Mori’s family. Yori and Iku’s mother, who shall henceforth be referred to as Saki, is obviously extremely uncomfortable, especially when they start talking about people they romantically liked back in college. Saki spills her drink, burning her hand and excuses herself to the bathroom where Yuugo promptly and creepily follows.

He makes uncomfortable advances and asks why she’s not wearing her wedding ring. Saki responds in a clearly very upset fashion that he knows it’s because she feels very guilty about their situation…..Wait, what?

She feels guilty about lying to her husband about Yori’s true parentage….so she doesn’t wear a wedding ring? I don’t get it. Is it that seeing the ring every day would remind her of her lies? I’d think looking at her son every day would remind her of her lies – especially since Yori looks so similar to younger Yuugo. Maybe it reminds her of the promise and bonds of marriage being tainted by her deception and disloyalty? Hm.

Yuugo gets even more forceful and tries to kiss Saki as she cries. Saki pushes him away and yells at him, but he gently wipes a tear from her eye and she runs into his arms.

….So…Yori gets his creepy rapey-ness from his dad and Iku gets her annoying crybaby ‘I’m attracted to abusive dickwads’-ness from her mom. I don’t know to respond to this.

Yori kinda sees them in their romantic moment, but they all return to the table like nothing happened.

The next chapter has Iku being unable to resist making out with Yori in a public library with tons of people around. You guys suck way too much at this. Do you want to get caught? At least now it seems more like Iku is legitimately in love with and physically attracted to Yori instead of just giving into his advances.

Yori has major suspicions about his mother and Yuugo’s relationship and is constantly haunted by Yano’s words from the previous volume stating that he and Iku might not actually be full siblings. Too excited at the possibility of having a full relationship with Iku, he runs to his parents’ bedroom during dinner to dig up some pictures to see if he can get some more evidence.

He finds his and Iku’s birth cards and discovers that Iku’s card is almost entirely blank while his is filled out properly. Yori starts suspecting that Iku might be adopted.

Continuing on from that scene, the last chapter starts with Yori finding college photos of his parents and Yuugo. As expected, teenage Yuugo looks almost identical to Yori. Despite not knowing what to make of Iku’s situation, he starts believing that Yuugo is his father, making Mori his sister.

The next day, Yori starts paying particular attention to Mori and even starts sitting next to her in class, making Iku jealous.

Ya know, if you take these scenes in another fashion, it’s almost like Yori is starting to become less attracted to Iku because he suspects they’re not siblings and is now attracted to Mori because he believes she’s his sister.

Would it really be a stretch? Think about it. The title is ‘I’m in Love with my Sister’ It doesn’t specify which sister. That would be a plot twist for the ages. ‘Yori’s not really a hopeless romantic – he just has a hard-on for incest.’

And remember what I said in my review of the OVA. A half-sister who didn’t grow up alongside him would be more believable and realistic in an incestuous relationship.

Yano confronts him about his behavior, knowing it’s upsetting Iku, and Yori basically tells him to fuck off because he doesn’t know what to make of any of this.

The volume ends with Yano whisking Iku away in a car and him about to do or say something to her.


The first part of this volume is hot garbage. I’m still stewing over Iku’s behavior after the near gang rape. I have never felt more enraged at Iku. And it’s so dumb because I should be directing all of my anger towards Tomoka, but I can’t because somehow Iku’s obliviousness and sheer stupidity eclipses those feelings at the moment, and that’s one impressive feat.

I have to wonder, as terrible as this thought is, would Iku have reacted in the same manner had Yori been too late? Yori still beat up the rapists and got expelled, everything else exactly the same, but Iku actually did get gang raped? Would she still friggin’ thank Tomoka for doing that just to get Yori home, no matter if she believed it was a master plan of hers or not? These shouldn’t be actual thoughts I’m having. These shouldn’t be legitimate considerations for a character’s actions.

Also, how horrible is it that Tomoka gets off scot-free?

It was at least nice that they remembered Takuma existed before Yori left the school…..I kinda hope they return to him in the last two volumes because 1) I’m way more invested in him and Mayu than anything going on in the main story and 2) They kinda just amputated his whole storyline with her if they end it here.

As for everything else, I fail to care, but at least the story’s getting kinda interesting. At least it would be if not for the fact that I cheated and already know their true situation. I am at least interested in what went down between Saki and Yuugo, because I didn’t cheat that far at least. It’s almost like they had a similar (though non-incestuous) relationship that Yori and Iku have. Yori/Yuugo comes on way too strong, seems creepy and rapey and Iku/Saki is such a useless crybaby twat that she can’t help but fall into his arms.

It’s hard to care about this ‘plot twist’ for a lot of reasons, but first and foremost is that I don’t care at all about whether this relationship survives, which is the only reason why the ‘Oooh are we really related?’ thing is even important. Yori doesn’t care about his parentage as a point of an identity crisis or wondering about his true place in his family, he’s not even all that interested in Saki’s current relationship with Yuugo – it’s all about whether or not he has a societal green light to pork Iku.

I don’t even know what to make of the ending cliffhanger. I don’t know what Yano intends to do or say to Iku in the car. It could be something sweet and profound….It could be another attempted rape or some equally creepy behavior. I think there’s a quota they have to meet. It’s a sad day when the latter of those options is the most likely.

Next time….eh, things.

….Previous Volume

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