I don't know. [he admits quietly, watching the Professor round the corner and disappear into the gray afternoon light. Then, grabbing Raph's fingers, he gives a gentle yet urgent tug to disengage his hand from Leo's arm.] Look, go wait at the bottom of the manhole, okay? I'll hide up here until I see him coming back. And if I tell you to run, you start running.

[He doesn't want to tell Raph that he's afraid the human might come back with a weapon, or even worse, some more "friends". Until those baked treats are in his family's hands, he's not assuming anything.]