There's a big difference between offering to resign and submitting a resignation letter with the words " irrevocable" stated in it. We may never know what really motivates Ruffy Biazon, head of the Bureau of Customs,to stay in his post, but the Japanese know fully well what "command responsibility" means and it is always linked to one's family reputation.
I understand where Ruffy is coming from--if he relents, the demons within his bureau would erupt into rapturous laughter. They managed to exorcise the bureau from its angel. Maybe Ruffy transforms himself into an archangel, like Michael or Gabriel, and unsheathe his flaming sword and swack the heads of these demons.
The bureau is simply too hard a nut to crack. Fact is, the very word "graft" seemed stuck in its name. Why is the Bureau of Customs so corrupt? Well, corruption is a "custom" already, right? Or, as what Ruffy says, "kalakaran" (customary).
So, give the guy some more space and time to salvage his reputation and his family's honor. Ruffy Biazon does not want people whispering around him that the only reason why he is still there in his post is that he is saving up for another senatorial dig come 2016 or he's probably trying to secure the future of his great grandchildren. Knowing him, he's not the type. He is too engrossed in his bible and his big toys that he's not the type that loves wallowing in a pool filled with billions.
Ruffy should fire all those grafters in his department, throw the book at them, and let them suffer the wrath of Baalshebub. And then resign.