I'm here to revive this thread since this is one of my favorite songs.
This song was featured in a live limited release called "kagerou no jiten ＜otona no shoten＞".
and if you own a copy of it you can see what all the "kore", "sore", "are" were about.
So he's like "Oh, I know you are actually ashamed of this, you are not pure because of this, and you are filthy because of this".
Basically the song is about how people fantasize about famous idols to the point that it becomes an obsession to them, sexually, not very romantically and delusionally speaking.
(「いつも以上に興奮覚えました」 → It means he got more aroused than usual after he watched a drama scene played by the idol on tv)
So since the idols get a lot of attention, people get jealous of it as they can't get noticed by the famous person in question.
(他のブタ野郎よりもずっと「キミのことは理解するハズだから」→ "I'm suppossed to understand you more than those jerks" refering to other fans)
Also this obsession leads to becoming an stalker, and in Japan idols get harassed by stalkers pretty often.
(1. 全部知ってます。→ "I know everything about you".
2. 頭の中はキミで溢れている。→ "I think about you all the time" *sexual connotation.
3. 触りたい。→ "I wanna touch you" *sexual connotation.
4. キミも結局汚いメスなの？→ "Are you a dirty whore too after all?" refers to jealousy, since she gets a lot of attention, she knows a lot of men, who she may have messed around with, idols don't make their way just for their talent, you know.
5. 気持ちのイイのはいつもいつも僕だけだし 少しサミシイ今日この頃です。→ "I can only get pleasure by myself, so it feels a little lonely to be like this right now" pretty much what happens to people when they masturbate thinking about someone who they want to be with but can't be be with, in other words, he can't sleep with her so he can only masturbate to feel good but it doesn't feel that good because he wants her really bad.
6. 僕は根暗な狂いセオリスト → "I'm an introverted crazy theorist" means actually "I'm an introverted harcore fan who day-dreams a lot", a theorist is someone who constructs theories, in this case it's used as someone who contructs a fake reality based on their twisted thoughts/obsession).
Daisuke it's representing it as fan x idol thing, but it's pretty much headed to the fact some bangyas get delusional af, just like what happens in "mousou nikki" for example.
But obviously, it's not only a vk thing, it happens in all types of industry, from j-rock, j-pop, to even av idols.
It exposes how some people act due to a delusional obssesion towards a person *regardless of which industry they're in* who is/may be "out of their league" but still hold into a little hope.
(キミはとっても人気者だから ボクのコトなんて知らない知らない。→ "You are so famous you don't even know about my existence").
(キミとボクは理想の二人だから → "We're perfect for each other" as in hoping they will get together someday).
That's pretty much how I see it.
