So I cleared the game this morning and it is one of the few (if not the only) videogame that features visible process on 3d models, I found it quite rare...
The process itself it's not a feast to the eyes, only showing her legs ...
It's impressive this series' effort to grant us fetish lovers at least visible process in all kinds of fields XD
The backstory of this character is quite simple: as Luffy, he wants to become the King of Pirates, but his old age reminds him the little time he has to fulfill his dream. So he travels to Transtown looking for a fruit that will grant him vampiric powers that allow him to drain their victims' age
Luffy is as well caught in an Old Age progression (from which he later returns to normal as well) but this is not the forum for it haha
https://youtu.be/q358KaP9ZwQ?t=12m53s - Watch the full vid to see both male TFs as well
About the game itself, I found it pretty solid. Kind of easy and with loads of One Piece fanservice battles and lines, but overall pretty fun.