Oh man stay away from this one. I'm not gonna be fancy here, this is more of a quick PSA than an actual review, but I could not stand by and let my fellow MAL users subject themselves to Kyoto animation essentially ripping itself off.
I should say first though that I love the original Kyoukai no Kanata show and Kyoto Animation in general so I'm not really reviewing the show here. Its just that KyoAni can't seem to do well with its show-to-compilation-film adaptations (I'm looking at you too Chuunibyou compilation film, but that's another story for another day). Why they feel the need to reinvent their existing works is beyond me.
Basically what we have here is the studio taking the original 12 episode series and cramming it into a sparse 120 min feature. The (many) small scenes that develop the characters in the original anime are mostly left out or completely removed in the movie, and the original show already moves blistering fast pace. We are then left with only the major plot events, and little to no context as to what's going on in the story or why we should care for our main dynamic duo.
I personally liked the series because of all the little nuances and goofy side humor that seasoned it, and the somewhat incomprehensible plot stood up for me because of how much I liked the characters.
So don't watch this wrung out version of Kyoukai no Kanata; it's like trying to eat an apple with no juice in it. Instead, watch the original series and give yourself the favor to THEN decide whether you like lolis with death weapons, siscons, 500 iterations of the word "Senpai" and all the other things that make this weird moe action combo meal a fun experience (or not).