Osamu Dazai is a kitsune who was the product of a human and a kitsune. The human, Mori Ougai, was a part of the well known Youkai Hunter Organization -- or, in the more well known name, The Port Mafia. How a youkai hunter and a youkai fell in love, Osamu will never know. Either way, that's how he came to be.

Unfortunately, the Port Mafia discovered the kitsune, but by some miracle, didn't find out about Mori's relationship with her or about Osamu, and by some terrible yet lucky coincidence, Mori was the one assigned to exterminate her - it only being lucky because if any other youkai hunter was assigned to it and showed up to find the kitsune with child... Mori would've lost more than just his wife that day.

It was a hard transition, of course. Thankfully, Osamu was too young to fully understand, and later remember much of his mother, but Mori was still in grief. Ever since that day, Osamu was living as a human with his father, where he could be kept safe. When the old boss of the Port Mafia died, Mori took his place and Osamu became his executive.

When Osamu was fourteen, Mori recruited an orphan boy his age with promising potential named Chuuya Nakahara, and the two became close friends. Mori was happy at first - Osamu didn't have many friends, let alone his age, so he was happy to see his usually reserved son making a friend. But then... Mori felt off. His son - his secretly kitsune son was getting really close to a hunter.

Mori knows he cant protect Osamu from everything, but... he was worried. He didn't want Osamu to end up like his mother. Osamu was his whole world, and he didn't know what he would do if something happened. So, when two years later, Mori got word from one of his trusted men, Hirotsu, that he had seen Osamu and Chuuya kissing and giggling together - holding eachother like lovesick teenagers... all Mori could feel was panic.

What if Osamu lets his guard down and tells Chuuya? What if Chuuya takes that information and kills Osamu for what he is? What if he tells someone? And the word spreads? His son will end up just like his wife, and there is nothing he can do to protect him. Sure, Chuuya is a good kid, but kitsune are one of the first youkai you're taught to eliminate on sight. Mori just doesn't know what to do.

So, it's only fair that, a few days later, the two find themselves on their living room couch as some sitcom plays on the TV when Mori asks. He couldn't help himself, really, as he blurts out, "Are you dating Chuuya?"