Amaterasu has the same things strapped to her arms in Person 4, what exactly are they?
Those are supposed to be Amaterasu's crest, which by itself is based on (very) stylized rendition of the old drawing where Amaterasu are depicted to don crown made of sun rays. In fact, Japanese crowns has that mini-sun to show that the Emperors (or Empress, the names are different too! Benkan for Emperors and Hokan for Empress) are alike to Amaterasu in position. Latter said decoration became the source of the Imperial Crest of Japan (the chrysanthenum crest).
