For Katie D. 

Standard Tuning
Capo First Fret

INTRO [x2]
e | -1----0------0-----3---- | 
B | -------------0---------- | 
G | ---0-0--0-0--0--0-0--0-0 | 
D | --2-2--2-2---2-2-2--2-2- | 
A | -3-----------2---------- | 
E | -------------0---------- | 

VERSE 1 (You can either keep repeating the intro it use these chords... vary the 
progressions as you want.)
          C                            Em                    
When the streetlights come on and the fireflies flicker,
     C                        Em
I am walking her home making plans.
         C                        Em
With her shoes in her hands, I am watching her dance,
       C                     Em
As the hem of her dress gently kisses the grass.


INTRO [X1]


D4         Am      F9        
 It suddenly rains on us,
D                D4            F9~
She is laughing and turns up her hands.


CHORUS 1
                  C                   G                    Am
Like autumn turns leaves, winter will breathe, cold on our necks, snow in
   F9
our paths.
             C                G                        Am
Wherever she goes, all that I know about us is that beautiful things never 
F9~
last, that's why fireflies flash.

INTRO [x2]


VERSE 2
          C                        Em
When this summertime ends, we will not part as friends,
            C                          Em
Things were promised in blood; we have sinned.
            C                          Em
Now there's tears in her eyes as she's screaming goodbyes, 
       C                       Em
I run 'long side the car turning numb to the sound.

INTRO [X1]

D4       Am           F9
I notice a chill in the air,
D           D4          F9~
September is creeping up fast.

CHORUS 2
                  C                   G                    Am
Like autumn turns leaves, winter will breathe, cold on our necks, snow in 
   F9
our paths
             C                G                    Am
Wherever she goes, all that I know about us is that beautiful things never 
F9~
last, that's why fireflies flash.

INTRO X1


BRIDGE
D4                 F9
 Innocence didn't mean we're immune to these things,
Am                       G
Let's blame the passage of time.
D4                        F9
Love and loss, truth it costs more than I can spare right now.
Am                   G
Maybe it's simpler to lie...

FINAL CHORUS

                  C                   G                    Am  
Like autumn turns leaves, winter will breathe, cold on her necks, snow in 
F9
our paths.
             C               G                      Am
Wherever she goes, all that I know about us is that beautiful things never 
F9~
last, that's why fireflies flash.

INTRO [keep playing to fade out]
Ooooh.... That's why fireflies flash...
Ooooh....

END

all in all it's really simple and like someone told me before, a "heart melter". 
tell me what you think, any criticism is welcome.