Of e21, one thing comes to mind about Aru's sense of pain -
If Pit-Aru says "ouch" when Haiba so much so as pinch him, getting shredded by the gears was supposed to be deathly painful. Aru was sort of fortunate there, because he Mascot head has already flown away from the body getting as it gets entangled and landed in front of Haiba.
Remembering Aru's recollection at e19 when Kurisu attacked him from back, it'll appear that his conciousness and feeling (including him) gets dumbed down the further the head gets away from his body.
I haven't read chapter 23.
But there is one small thing that had been bugging me... why does Aru's homeroom teacher care about him so much? 0_0
It is said that he comes to visit Aru everyday with a worried look. I mean, even if Aru is his favourite student normally a teacher won't care that far.
On other 2ch news (LOL), someone said there must be something going on between Aru's Mom and the teacher.

Aw, how come we never seen Aru's own Dad visit him!?

(Take my words with a pinch of salt..... ^_^; )
A boy!? Seriously?

With all his/her head garb and necklaces and what not I was so sure he/she was a girl...

But then again, his/her name is Suuki Kei. I guess Kei is more commonly used as a guy's name, though I've heard of girls called Kei too, albeit much rarer. I'll assume he is a guy from now on, too, then
Well, he is a boy, or at least 99% probability ^_^; , from the way he talk in Japanese.
Besides,
this author has a named all male characters appearing so far with Katagana and all female characters with Hiragana. And the Kei has a Katagana name.
Cursing people would be an interesting talent. I mean, if he can have whatever he says (curses) come true, then the possibilities are just about limitless...
...
Why would Enigma want to provide them with a helpline to the real world? Sooner or later the connection is going to get cut, I think, but maybe Suuki will continue to try and help from the outside (if he even can do anything...).
I wonder if Enigma needs a problem solving person on top of a bunch of super power tennagers to do his bidding. Occult maniacs are not that rare compared to superpower teenagers, and quite substitutable (any curious Occult-Maniac can investigate but Haiba-tachi's are all Unique Powers) so Enigma perhaps just invited one without coersion.
On the other hand, if his curses are for real, Kei may have some "potential" that later evolve to become full-blown powers that Enigma would want to coerce in later part of story....
Just read Chapter 23.
In other news it looks like we'll get Takemaru's backstory soon. I'm interested in what his power is.
I'm also curious to what Takemaru thought about his mostly-likely-present power. I've long suspected he actually has no knowledge of his own power from chapter 4, otherwise he couldn't have called Moto a freak after he was told of Moto's "disappearing" power. .......Or, Takemaru have a slight idea of himself being "something wrong", but lived in total denial.
I'm more interested in Takemaru's connection with Aru's teacher. And I hope Aru's teacher doesn't turn out to be Enigma. That would be so out of left field. But he always seems to be popping up for some reason.
My wild take is that he's on the side Enigma's against. And even if not, him being a saintly, caring teacher is just a false front. And an innocent boy like Aru could never suspect people who encouraged him.