My Soren character can do that with his entire body. The human form he takes is the real costume.
Rowan: "Well at least if something goes wrong she can't blame me..." *pokes it* "No biomass to affect."
*SW watches as Rowan is slurped into the ecto/warper pocket dimension
Rowan: *muffled* "Well...that was unexpected..."
Rowan: "Hey, Shadow, mind if you open a way out for me...oh hey, is that an XBox One? I didn't know you had a rec room in here..."
I'm picturing a poor Manifestor/Warper with semi-sentient shadow-ectoplasm tendrils... every time she subconsciously dislikes her outfit it starts taking big bites out of it, replacing it with shiny black latex replacements...
Definitely someone you don't want to get on the bad side of!
Sara: "Fuzzy boots!" -grabs Shadow-Wraith's calf and nuzzles, purring-
She's better hope she doesn't get paired against someone who can dispell her manifestations for her combat final.