Board Thread:Naruto Discussions/@comment-1512913-20170121174919/@comment-1872728-20170122093739

@Elveonora The back marking is just the Six Paths: Ten-Tails Coffin Seal marking, similar to the stomach marking of the Eight Trigrams Sealing Style on Naruto, or the shoulder marking of the Iron Armour Seal on Killer B, or any other fuinjutsu that has a visible marking.

Regarding to Kaguya having SPS or not, it's only normal that she does since she did eat the fruit which contained most of the Natural Energy on Earth, and also the first source of Sage Chakra on Earth.