How do you even erase someone's existence? In the digital world, there are records everywhere, even if these guys are still in the late 90's. Do digital records disappear as well? If you simply remove a digital entry by force, it would cause variable errors elsewhere in the database. You would need to fix that as well. Backups would need to be altered naturally. You'd also need to remove all the physical belongings of the erased person. Basically the only viable method to achieve this is to rewrite the history itself, as if the person never existed in the first place, so all the records and other traces never existed either. If the entity behind this all has the power to do that, they could also make Namba disappear entirely, probably with but a mere thought. Dude better hope they won't consider him a nuisance, unless he has a divine protection granted by the goddess who sent him back.