Lyrics for Shakugan no Shana Opening 2, being by KOTOKO. Some people aren't a fan of this song, but I liked it enough to try and make sense of it. This translation should hopefully be pretty accurate. I also put together a romanization below.

KOTOKO - being
lyrics and composition by KOTOKO
Translation by Blitzwing01

高鳴る鼓動　触れあう現世(いま)選んで
進め　時の果てへ
Choosing the throbbing beat that touches this world
Advancing to the end of time

ぽつり虚空の夜につぶやいた
「また、明日ね」って言葉
燃え巡り照らす太陽のような
強さと永遠に焦がれた
Under the empty night sky I quietly muttered
The words, "see you tomorrow"
I yearn for strength and permanance
Like the burning shine of the sun

たったひとつ残せるなら
存在を抱いた　この瞬間の笑顔
ただひとつ守るべきは　君の未来
But if there's one thing remaining
The existence embraced, this fleeting smile
If there's one thing to protect, it'd be your future

刹那　揺れて軋むこの世を選んで
ずっと運命の地を翔る
芽生え始めた炎　胸に秘め
今世(いま)を　来世(あす)を　君へ
In an instant, choosing this shaking unstable world
Always flying in the land of fate
Hiding the flame that lit in my heart
Sharing this world and the next world, with you...

細めた目の先に浮かんだ
果てしなく広がる空
翼見つけた君の背中が
遠ざかってく幻を見た
The squinting eyes from before came to mind
The boundless expanse of the sky
Discovered the wings on your back
Like watching a distant vision

そっけなく装うたび
鈍い音で潰されてく何か
それぞれに灯(とも)した色
交差させて
Wearing simple socks
With a heavy sound something smashes
Every light's colour was
Intermingling

かけがえのない君と現世(いま)選んで
ずっと夜に虹を架ける
確かめあった強さ　時間(とき)に変え
空を　海を　越える
Choosing the irreplaceable you and this world
Wearing a rainbow every night
My power rising each time
Sky and ocean to cross

高鳴る鼓動　触れあう現世(いま)選んで
きっと運命の理(り)に生きる
いつか消え行く炎　願いに変え
夢を　来世(あす)を　君へ
空を　海を　越えて
Choosing the throbbing beat that touches this world
Surely it's fate's reason that I exist
That someday my flame will vanish, I wish this to change
Dreams of the next world with you
Crossing sky and ocean...

Romanization:

takanaru kodou fureau ima erande
susume toki no hate he

potsuri kokuu no yoru ni tsubuyaita
"mata, ashita ne" tte kotoba
moe meguri terasu taiyou no you na
tsuyosa to eien ni kogareta

tatta hitotsu nokoseru nara
sonzai wo idaita kono shunkan no egao
tada hitotsu mamoru beki wa kimi no mirai

setsuna yurete kishimu kono yo wo erande
zutto unmei no chi wo kakeru
mebae hajimeta honoo mune ni hime
ima wo asu wo kimi he

hosometa me no saki ni ukan da
hate shinaku hirogaru sora
tsubasa mitsuketa kimi no senaka ga
tooza katteku maboroshi wo mita

sokkenaku yosoou tabi
nibui oto de tsubusareteku nani ka
sorezore ni tomo shita iro
kousasasete

kakegae no nai kimi to ima erande
zutto yoru ni niji wo kakeru
tashikame atta tsuyosa toki ni kae
sora wo umi wo koeru

takanaru kodou fureau ima erande
kitto unmei no ri ni ikiru
itsuka kie iku honoo negai ni kae
yume wo asu wo kimi he
sora wo umi wo koete