From what I can see from the spoilers, seems like mother would misunderstand then blame Ha...

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When was the video made? Was what they were doing consensual like the first few times or was it flat out (obvious) rape? Because it'll obviously made a difference to the mother depending on which it is

It was at the beginning. Haruki was giving Hikaru a blowjob so it does not look like rape at all ='( That's probably why Hikaru was blackmailing him with this video, it would have been strange to show their parents a proof that he is raping his step-brother. I don't think this will make the mother understand that her son is a rapist... (well, maybe Hikaru has several videos on his computer. In that case, there is still a chance to have at least one video showing that Haruki was forced to do it).

My biggest concern is victim blaming. Even if senpai found out. It obviously does excuse the younger brother's behavior, but the fact that the elder brother originally allowed it, some may argue that he "had it coming."

Or that he "led him on."

I was thinking the same when I re read the chapters .The first time when hikaru tried to molest haruki he wasn't actually sure what just happened and thought may be he misunderstood but I didn't get the blowjob part? Obviously he didn't liked it may be it was because he wanted to understand the problem haruki was facing so he went with the flow at that time .But in next chapter if there will be something like that where the video will show haruki giving him blow job.that will go against haruki or there will be some comments about how haruki is the one to blame to not shove hikaru off from the beginning

I think Haruki was a bit naive in the beginning but he did not expect it to go that far. He saw his brother was troubled and knowing he was the only one Hikaru was open with, he tried to help. Appeasing Hikaru sexually was not the best way to help but again he did not expect it to get that far. Haruki knew how sensitive Hikaru was and may have been slow to respond because he did not want to hurt him further. That probably is why he was less direct with how uncomfortable he was (while it was subtle, he did let Hikaru know he didn't like it even then though). If Haruki was aware that Hikaru would eventually start raping him, he may not have done what he did.

Ah thanku i was unable to fully understand the situation but I do now .And the more I read the chapters I got know how pathetic hikaru is he just behave like a psychopath damn he is scary actually very scary the way he blackmailed haruki and and treated him gives me chill maybe some people will say that he didn't know what he was doing but the way he react he know everything what he is doing he just don't give a shit about it . Just like he said about the things to shut his heart so he don't have to feel guilty anymore

Yeah. Hikaru is fully aware that Haruki is not okay with him raping him. If he was under the impression Haruki was fine with it he wouldn't have blackmailed him and he wouldn't have continued raping him after seeing the damage it's causing. He's very selfish and fears Haruki leaving him more than anything. So as long as raping him keeps Haruki focused on him, even if it is out of hate, he'll keep doing it.

The source of Hikaru's guilt in chapter 2 still confuses me. I made a topic about it here http://www.mangago.me/home/mangatopic/1637963/ But if nothing else his guilt there shows he is aware that he does can cause other people harm. I guess since closing off his heart, he no longer feels guilty for that harm other people endure because of him, even if it is Haruki.

Yeah actually. I was re reading this manga today we don't have full explanation for hikaru's guilt actually we don't know about his past much except for the fact that he was harassed by the women and he is disgusted by them . He wasn't actually wanted to be friend with the guy who was his classmate and was going with the flow or was thinking of how the friendship work between two people so that's why he started to talk to him .The only thing that come to my mind is when his friend's girlfriend proposed him and saw his classmate he looked a bit upset .But only for that to shut his heart is that ok! Or maybe he it was his first time having some called as friend but that got ruined so he lost all the hope and thought no matter what he will do people will be hurt by his actions .Well we don't know the reason why he said that it wasn't given I guess

I didn't get the impression Hikaru considered Nojima a friend and it's not like friendship was something he really desired. There's the possibility that he valued their relationship more than he was willing to admit, he did share his feelings about women with him after all, but if that were the case I feel like it could have emphasized it more. I think it's a small plot hole but from what we're given his failed "friendship" with Nojima was the only possible source of his unbearable guilt.

Yup that what I think too