The Evil Men Do
If anything were mine, Sweeney and Lovett would have lived happily ever after. So obviously not.
I took a few liberties with Toby's past. I realize he said he had no mother, but I'm changing that little detail because I feel like it.

Tobias Ragg wasn't smart. He both knew and accepted this. Growing up he had never been given the opportunity to learn much aside from what was necessary to facilitate his own survival. Most of his life had been spent in the workhouses where he learned to work hard and keep his mouth shut if he wanted to avoid a beating. (This proved a valuable lesson once he began working for Signor Adolfo Pirelli. He couldn't avoid the beatings altogether, of course, but he soon realized if he worked hard and kept his mouth shut they would be far less severe.)

Toby may not have been smart, but he wasn't stupid either. He had suffered much in his few short years (and he wasn't complaining, because who hadn't?) and he learned early on how to adapt for survival. If nothing else, he could never be accused of being naïve.

He also learned how to recognize evil when he saw it. He'd seen enough impiety in his young life to understand that a certain glint in a man's eye meant there was something devilish beneath his exterior.

He remembered seeing it in his father's eyes when he we raised his fist to his mother that final time. He'd seen it in the faces of the masters of the workhouses as they pushed him and the other children to work beyond their physical limitations. He had seen it in the eye of Signor Pirelli when the barber would punish him solely for the sake of punishment.

Yes, Toby had seen enough evil in his lifetime to recognize when he was face to face with it. So when he came to face Sweeney Todd the boy was not fooled.

There was something off-putting about Mr. Todd, Toby sensed it the very instant they'd met. He tried to ignore it at first. After all, Mrs. Lovett seemed to be fond of him, and if she saw something in him then Toby reasoned he couldn't be all bad. But it didn't take someone smart to notice the number of customers going up didn't always match the number coming back down again. And he had spent enough time working for Pirelli to know there really was no need for a barber to have to change his shirt nearly as often as Mr. Todd did. Toby couldn't imagine how simply shaving a man could be quite so… messy.

So Toby concluded that there truly was something evil about the man. Sweeney Todd may have fooled everyone else, but he wouldn't be fooling him.

Toby prided himself on his ability to see through a man's lies. He had seen through the Demon Barber and knew he had to convince poor, dear Mrs. Lovett of the utter transparency of it all. So trusting and so caring, she was blind to the evils so dangerously close to her.

He wasn't surprised when she didn't believe him. He wasn't surprised when she tried to defend her dear Mr. T, wasn't surprised that she didn't want to hear the wicked truth about the barber.

Toby was surprised, however, when he bit into the fleshy digit baked inside his meat pie. He was even more surprised to discover the grinder filled with severed limbs and assorted parts. But what shocked him the most was the soft click of the lock sliding into place on the bakehouse door.

It occurred to Toby then, as he hid himself in a sewer grate on the bakehouse floor, ignoring the pair of voices calling his name (Nothing's gonna harm you), that his earlier pride had been greatly misplaced.

He could spot the evil in men, no doubt. But it would seem, when it came to women, Toby was still grossly naïve.

Demons will charm you with a smile.