In that moment they both said "i love you"... Normally, their lips would entwine and they would hug and embrace each other, but as both Luna and Neville were out of the ordinary, then obviously their love story would be out of the ordinary.
So, once they both said i love you, they both burst out laughing, but although they were laughing so loudly, they just couldn't take their eyes off each other, then Neville took Luna's hands, their hands clasped, and Luna felt a flash of heat sweep across her face, however her cheeks were already quite rosy but this time they went bright red.
As Neville took one pigeon step closer, Luna looked down out of embarrassment, (she wasn't too good in these situations), Neville lifted her face so their gazes meet, but as it was the first day, Luna was dragged away by the fellow girls of Ravenclaw, and they all left giggling, all except Luna, who just couldn't stop looking back.
Now, we all know how dopey Neville Longbottom can be so, as he was walking backwards trying to keep his cool, he tripped and fell on his bottom. And then numerous people were asking, "Or righ' there Neville, wonder what's goin' on in that 'ead of yours?"
Of course, he knew that Luna was still watching but his only reply was, "oh n-n-n-nothing, i-i'm okay" and he jumped back on to his feet and went red through embarrassment, after all the love of his life was watching this whole conundrum. Little did he know that Luna was actually more attracted by these so called 'incidents'.
And so both Luna and Neville, turned around, with Luna blushing and smiling, and Neville ruflfing his head and smirking, they both parted their separate ways.