KHR: Noticed Only When Needed
It all started with a single letter, a letter that was left behind by the woman who never came back.
'I'm not coming back, I found someone who I truly love, and loves me back.
And he was always there when you were not, comforting me when you, Iemitsu, never bothered to visit home.
For Tsuna, who was only 5 at that time, already understood what the letter had meant, because unknown to everyone, he has always been adept at learning everything.
A/N: if you want to know what happened after Nana left, then by all means, read ;)