i want #15 to stay a black mound but i want to know his looks too!!!!!! what do i want!!!!

You want him to be able to change to human but also be able to change back

kinda.. like I want maybe a glimpse of his true self in the past maybe?? because it would be weird to change from normal human to back to the black mound without some reasoning... ┑(￣Д ￣)┍