It's a happy ending. Neither characters died or are ghosts. The father finally died - hence why they're both in black after his funeral and the black haired dude asking the bruised up blond why he let the dad beat him until the end - He then asks if they were still kids in reference to the time they were caught which led to them being separated which means they are both no longer kids but are now adults (Ghosts don't age).
The black haired guy never forgot his love and planned for the day he could be with the blond again by saving up to build their life together and he's come to fulfill that now that the father is dead and is happy to hear the blond still loves him.
In the last panel the black haired guy gives the flowers to the blond who tosses it onto the grave to symbolize that it's done, he's paid his respects to his father and is now moving on to be with who he wants to be. It's why the black haired guy lightly says "good grief, well well" they're out of shot but probably embracing and in the end the pretty flowers are left behind on top of the ugliness that was the father in an almost bittersweet moment.
If it were a drinking game to take a shot every time you read "wallace" I'd drink myself into a coma