Raph often watched the world above ground from the safety of the sewers; determined that he'd get to go topside whenever he wanted someday.
The first time they'd ever been allowed to leave the sewer was because some madman, Baxter Stockman, had accidentally destroyed the lair. The roof had collapsed between them and splinter and they had to go topside to find another way to get to him.
As soon as he set foot in the dark alleyway he felt free. He loved his family, but he hated being trapped underground. Life in the sewers wasn't enough for him forever.