Cha hae-in since i dont really like the romance ending in the original and hae-in can be a great partner for the mc đ¤đ¤plus training together in swordsmanship can definitely a good time for them to develop
oh if you gonna travel to onepiece author
I have a suggestion don't make the mc join Luffy create a crew for him but I think it's pretty useless because his gonna go travel worlds what do you think author?