It is a Japanese cover of the Eurobeat track "Dreamin' Of You" by Lolita. 2. Season 1, Episode 8 (Live Action: " Worst in the East ")
Luffy defeats Arlong, destroys Arlong Park, and officially receives his first bounty poster, setting the stage for the journey to the Grand Line. [S1E8] Belief
The episode also features a confrontation between Luffy and his grandfather, Vice Admiral Garp , who eventually gives Luffy his blessing to pursue his dream. It is a Japanese cover of the Eurobeat
The eighth and final episode of the first season of the is titled "Worst in the East" . destroys Arlong Park