Jolny

That jacket looks like Cole McGrath's!

Then, those army guys barge in and I'm not sure what they're saying. Then Lightning says to that young dude that he can run away and doesn't have to die.

And then in the middle when that dude (what's his name lol) comes running up to the young girl he talks about some mission and he wants them to do it together. Then Lightning is talking to someone saying how she wanted to grow up fast to protect her little sister after their father died. She mentions that she threw away her actual name and took the name Lightning because she thought that would help her grow up faster :S
And then she says it didn't help but rather hurt her sister.

Blah blah blah, then that young dude is with some old dude (his father?) and says he'll leave after resting a while, and his father replies "your life is here!"

... anyone wants me to carry on? :S

The talk in the beginning seem to imply that the loli girl is Lightning's little sister. Maybe what the dude is saying is that Lightning will be his big sister (sister-in-law), since he's lovey-dovey with her sister?