* In the manga, Koshiro has a bout of curling into fetal position, rolling around on the floor, and smashing his head into walls after finding out Nanoka, who he has essentially just had a date with, is his sister. It's drawn in such a way that it would be outright hilarious if not for the tragic and unsettling circumstances of his situation.
** In general, the manga actually has a habit of drawing exaggerated, comical moments and expressions that help lighten up its mood. This is especially true in the earlier chapters before things take a turn for the serious, although these types of moments continue to crop up for the duration of the series. The anime in contrast, has a much more consistently solemn tone to it.
** In the anime, we have our main...couple's reaction when the big reveal is finally dropped--they stand there staring at each other in silent shock, mouths agape, while their dad obliviously tries to make small talk with them. You can tell both of them are screaming internally.

* At one point, Chidori catches Odagiri none-too-subtly coming on to Nanoka and whacks him upside the head with her purse, sending his glasses flying and leaving him helplessly floundering and groping around on the floor for them.
-->'''Odagiri''': My glasses...! My glasses...!

* The point at which Nanoka gets to chattering a bit too freely about her big brother to a boy while helping him store some equipment, and he rather casually says "So it's true what they say: you really do have a brother complex." A cloud (of steam?) forms up over her head, and pops like a balloon.
-->'''Nanoka''': ''What!?''