Oups mistake "want"
Its in the afterword. Harutomo went back to Japan and opened a own small restaurant. I'm guessing Kazushi went back with him.
Seems like a shame to me that the went back to a homophobic country. In the US they could marry and even adopt a child. Opening a restaurant is also fairly simple here. No need to hide your sexuality - particularly in big cities - and no "hetero marriage means happines" pressures. So, other than missing their "home country", I can't imagine why they'd go back.
In the end will they stay in america or go to japan? So cute story wanr more