Lon thanks for your reply!! Maybe I wasn't being clear enough in my original post, whoopsies.
What I was looking for was if the Grell outfit could fit the Slim Male Obitsu because I'm making customs to go along with the Azone Asterisk*Collection releases of Ciel and Sebastian. So far I'm working on Alois and Claude in the Azone style. I was hoping the Pullip version of Grell might fit the slim male Obitsu because of this. Grell is such a complicated costume that I currently only trust one seamstress to really satisfy me (her Alois custom outfit just...oh, I hope when I debut him it brings business to her shop because she truly deserves it for being such an amazing person as well as a seamstress who can work magic!) and she's backed up BIG TIME all the way through February, not to mention she's already working on a smaller custom and fitting me in purely because we've become good friends. Like I said in a post above, Grell and William are now officially on the back burner for now. Good enough because I also want to complete Agni and Soma and while I found a beautiful Golden-brown Taeyang whose body will do nicely for Agni, I'm still stuck for Soma without any bodies that remotely have that skin tone. I'm desperate enough to try dying the darn Obitsu.