Comments: Following ebossert's rec, I checked this out. It is a very good looking film, nice soundtrack, smoldering ambience. It's rather arty in its cinematography and set pieces. I didn't mind that the j-pop idol boy who stars can't act yet, until the final act wherein the film seems to plummet. It wasn't because of j-pop idol boy's acting, but right when the film is about to do its reveal everything else seemed to try and stay in tension building mode with the result that a massive gravity weight prevented the film from any finale. The acting got really bad (that other young weirdo's exit from the coffe shop was horrendous), and the script jumped into "OK, time to wrap things up ... anybody got a twist we can use?" mode.
It's worth seeing for fans of mystery/thriller/death-love goth stuff, but I think there's a reason this film's been out for a couple years and nobody's heard of it.
Summary: High school students Itsuki Kamiyama (Kanata Hongo) and Yoru Morino (Rin Takanashi) share an odd fascination with human cruelty and murder. Kamiyama knew they would share a connection as soon as he noticed a cut mark on her wrist. Together they track a brutal serial killer in an attempt to find the latest two victims -- not necessarily to help bring the killer to justice, but simply for their own morbid need to inspect his or her handiwork.