Was thinking about this question of why GACKT used kanji+katakana instead of kanji+hiragana and since I’d seen the video relatively recently it occurred to me that since this arc of the MOON SAGA takes place in Europe, it could be that he did that to show that the character singing isn’t one of the Japanese originators of vampires but rather a European one. Because the other use for katakana besides emphasis or historical uses is to show that a) a non-Japanese character in a work of fiction is speaking Japanese for the benefit of the Japanese audience but within the story line should be understood to actually be speaking whatever language would be appropriate; or b) to show that a non-Japanese person is speaking Japanese (regardless of whether they’re speaking it well or not—kinda the same way that sometimes American TV shows put captions on people speaking English if they have an accent even if it’s not heavy). In these cases it is more common to write everything in katakana, but mixing in kanji isn’t unheard of either. Sasazuka Elise comes to mind.
Personally I prefer to think he did it for emphasis because unrequited or otherwise unfulfilled love is a particularly strong and sucky emotion, and because I find the practice of writing what non-Japanese say in katakana discriminatory (though I can cut Usage A some slack). But given that GACKT’s always talking about how each song portrays a character, I think the possibility that he meant for this to be a non-Japanese character’s song is also possible.
There’s one other thing I’ve wondered about this song, and that’s the weird beep at 3:40, right behind GACKT’s vocals as he’s singing “kimi no na wo.” I hear it on the CD and on MP3 and AAC rips of this track. It sounds very similar to one of the beeping noises the old iMac G3 had. It was one of the sounds you could use as an alert. There’s at least one other instance of a Mac sound in GACKT songs in weird places, namely at 2:37 of “Kimi ga Matteiru Kara.” I had that chime noise set to announce the quarter hour on the old family iMac. I’m pretty sure there was one more song with one of these sounds, but alas, I’d written these observations into the comments section of iTunes on my now-dead MacBook Pro. I’ll try to remind myself to write things down next time I hear these beeps & chimes.