The game's structure works as follows:
After the Day 3 in-game, every A and S rank answers can lead you to special routes that can show you more interactions with the characters. Eventually their interaction start being more intimate but not by a lot.
There's also PLOT routes but to achieve them you need to answer only S-Rank routes. For now though, only patrons have access to a cheat-sheet, and recently the game got updates on Patreon that gives you a message that displays the mood of the character based on what you answered, each rank answer gives a different notification so it's "easier" to know when you answered something very good or stupidly bad.
Thanks for enjoying the game, don't forget to share the version here toe everyone else, and hey if you ever feel like supporting the game, Teir 1 members get their names on the game permanently and also get early public versions. Right now, Tier 1 members can access to early 0.58 build of the game, while by the end of this year (December), the game will be updated to this version only in December, while by June Tier 1 patrons will already have the build 0.63 available. Tier 1 patrons will be exponentially more updated than the public in that regard.