He's not supposed to hang a lantern for her, because she's not really dead, she never existed in the first place. Azula, prim and proper and (smirking), puts one up outside her bedroom to honor dear Grandfather's memory; Father, as cold and remote as the Water Tribes, glides past the decorations without a second glance.
"She loved purple," he murmurs to Mai, by the turtleduck pond while the rest of the palace revels. He has never felt more hollow, tying the strings to a tree branch, watching his sad little memorial flutter in the breeze like an oversized plum. She deserves so much more than this, from the boy who killed her.
"I'm sorry she's gone," Mai says quietly and peppers his face with kisses, nose and cheekbones and forehead.
The tears begin to fall, then, but she doesn't laugh, not once, just holds his hand very tight.