While playing the game using the game scripts to see which were the options that increase other characters' affection, I realized there is an error, or at least what I believe is an error.
On the second day, when MC goes to the saloon, he meets with Charlotte and participates in her tea party. If he chooses to spit the tea out, Charlotte's affection increases, but will get mad and uncomfortable. On the other hand, if MC pretends to like it, Charlotte seems to be happy but her affection nor increases or decreases. I don't know if this is how it was intended by the developer but it is tricky for the ones who just play the game and want to increase her affection by selecting the most obvious option. I think this is an important matter because of how this interaction affects the next one on that same day.
When MC returns to the manor after witnessing a man being judged in town and goes to the right hall on the second floor, he meets with Charlotte again and, as they talk, MC has the option of telling her he was "Just wandering around". If MC chooses to say this, depending on how much affection Charlotte has towards him and if he did or didn't spit out the tea, she may or may not give him hope of entering her room the next time they meet.