"Urouge: You hurt me pretty badly.. don't think I am the same as before! Inga Sarashi!!
[In a nutshell, it means expiating in this life the sins committed in one's former existence. It'd be easy to conclude that Urouge is dealing back the pain that Kuma inflicted him]"
Apparently Urouge has some technique that lets him pump up more the more he's hurt. Don't know if that's some monk thing or a Devil Fruit, though.