I wanted to have Jin's skills to be able to put an end to the Rio and São Paulo militias that are in state governments (and those who supported them in power).
Dude, please read ALL the comics, not just the pictures where someone gets shot or has breasts. The story itself already shows that Ijin began to remember part of his past there.
It’s likely that his mom was affectionately calling him ‘Jin-ah’ as per a Korean nickname, with ‘-ah’ being like a term of endearment. Thus, he’ll think his name is just ‘Jin’. (☞ ゚▽゚)✧☞