Opportunity Arises

Shota Aizawa and Hizashi Yamada have been engaged for 3 years before Hizashi took a job opportunity in America. Hizashi left, promising to return to Shota. But after 15 years Shota has given up on life. He becomes sucidal and a acholic. He pushes away everybody, afraid of being abandoned again.
Then he gets a suprise visitor while singing at a karaoke club. Will he give love another chance?