Trying to find this damn song...

Okay, so, I have this song stuck in my head.
Only, out of this ten minute or so song, I only have like, a 30 second clip of it stuck in my head. And it isn't in english.

I know the translation off by heart, but it hasn't helped me yet.
I love it regardless. It's such a haunting melody, but so catchy at the same time. Makes me want to sing along. But ugh... what is this song called?! DX

Won't anyone play with me?
I'm so fed up with this monotony,
I might just do something mischievous.

Butterfly, butterfly,
Shall I tell you where the water is?
Sweet or bitter water...
Just choose the one you like best.

AUGH WHAT SONG IS IT?! DX
I've been youtubing like mad, and I'm slowly getting there.

I know a few things about this song that are kinda helping;
It's Japanese. There goes 90% of the songs I know.
It's from ONE of the 8 Rock Musical Bleaches. That narrows my search down to... 184 songs.
One of the captains sing it, which narrows it down to... about 90 songs or so.

I'm going to be on youtube all night, I don't care, I'm finding this damn song! DX


EDIT: FOUND IT OMG FINALLY.
Skip ahead to about 2.06 or so, and watch until about 2.26.
Seriously.
this. part. won't. leave. my. FUCKING HEAD. DX


EDITEDIT: I found another translation for Gin's bit where the last part is something like "Butterfly, butterfly, what kind of honey do you want? Sweet or bitter, I'll give you both either way" or something like that. I like the translation above better, obviously.