The Dragon King Slayer of Kuoh

Ryuga Dracul when he was 5 his dragon blood was awake and got teleported in the underworld and he was raised by Tannin, during that time he met and became friends with Shirone and Kuroka until he was 10 and Kuroka awake her senjutsu to save him and Shirone and he escape with kuroka because the devils think that she was got berserk, before he leave he give a hug to Shirone and made the promise to meet again. 7 years has passed since that day and now Ryuga is with Vali and her team, how all the factions will react when they sense that the dragon king slayer enter in their territory ?