Train Me, Please (An Riren Fanfiction)

How would life be different for Eren if he grew up in the same hell of darkness that Levi once grew up in? What differences in his life would this hold?

As a young boy, Eren grew to learn how to battle out every trouble on his own in the streets through various methods of pickpocketing. Once older, Eren happens to stumble across a young girl and young boy, who he takes in and takes care of.
Times grow darker and tougher in this hell hole, and new methods are needed to be taken up to gain food and money. Trained and dangerous, the three always go out here and there for a bit of "extreme pickpocketing" one would say. But on one of their missions, what happens when it isn't the military police that sneak up on Eren and his crew, but none other than the Survey Corps?

This will contain smut. Don't like? Don't read.