It's already a series, which is why it has more chapters compared to the other stories, it means that this author was succesful enough in getting their story picked up OR, this author is already a succesful one and they've been invited to join this anthology series to write a story.
FLOWERY! PATH ! OF! EVIL! SHOULD HAVE THEIR OWN SEIRESSSSS (as reiterated by many commentators with the same intention as mine )