Ranking

The ranking system of Happy Birthdays is how the quality of entities is represented in-game.

Summary
As shown in the example attached to this page, rank in Birthdays the Beginning is presented in a Japanese-style ranking system. While this system is somewhat unfamiliar to many western gamers, it's very common in Japanese games, especially in the mobile space. The system ranges from SS to F, with SS being the "top mark". This is different from the western system, where "A" typically denotes the highest score. In this system, A is typically considered around 90% completion or the value being better than 90% of the other values - 99% would thus be "S", with anything 100% or greater would be considered "SS".