Shachi and Penguin were bad boys in Swallow Island in North Blue.
Bepo left Zou 14 years ago and chased his elder brother. He then got on board the ship which was heading for North Blue. He was wandering in Swallow Island 13 years ago.
Law witnessed a Polar Bear who was bullied by 2 bad boys. The bad boys picked a fight against Law, but Law beat them up. The bad boys (Shachi and Penguin) and Bepo were attracted by Law.
When they first met:
Law was 13 years old
Penguin was 15 years old
Shachi was 14 years old
Bepo was 9 years old.
Bepo studied navigation skill hard since he wanted to come back Zou.
Oda says he doesn’t have an intention to draw it in manga.