In the Canis series:
V.1 - Dear Mr. Rain
Kutsuna Satoru, a hat maker, picks up a man collapsed on the side of the road named Kashiba Ryou, who came to Japan to die.
V.2 & 3 - Dear Hatter
The sequel to Dear Mr. Rain.
V.4-Current - The Speaker
A spin-off the main series that follows some of Ryou's gang acquaintances.
Note: The latter chapters contain explicit content, so don't change the genre to shounen-ai.
HQ, comics, mangá