Survivor's Guilt (слэш)

“I never apologized," Sirius say.
“Don’t worry about the cake," says Remus automatically.  The cake that Sirius had tried to bake with Harry. The one that blew up after, well, after god only knows what Sirius did to it.
“I didn’t...I didn’t mean the cake."
Sirius ducks his head and plucks at the hem of his shirt. “I never apologized for believing you were capable of selling us out to Voldemort.”
His stomach turns to lead as he breathes in through tightly clenched teeth. “Oh."