How spicy is each book in the Zodiac Academy series?

smutrecs.com has rated 2 books in the Zodiac Academy series by Caroline Peckham: Book 5, Cursed Fates (about 4/5); Book 8, Sorrow and Starlight (4/5). Not listed here: 6 earlier books in the series.

1. 
   Book 5Cursed Fates spice about 4/5
2. 
   Book 8Sorrow and Starlight spice 4/5

Each book page lists the sources behind its ratings. Ratings marked "about" are estimates. How we rate