Why does Bimbo return to the city after getting Tito safely to the marine gate?

Bimbo returns to the city after ensuring Tito reaches the marine gate because he feels a strong sense of responsibility and loyalty to his community. He understands that his work is not finished and that there are still challenges and dangers to confront. Additionally, Bimbo's return reflects his commitment to protecting those he cares about and the desire to confront the ongoing struggles they face together.