Hello! I've been playing the game for a few days and I've taken some notes. Some of these points can be seen as nitpicks, but it's your game so you get to decide what to change or not.
- Influencing seems a little slow. I would think about increasing the influence amount. And maybe increasing it even more during sex? Just a thought.
- What counts as Massaging? I'm not sure what that's for. Handjobs, hugs, and most other "hand" interactions count as caressing.
- I mean no offense of course, but it seems English may or not be your first language. I recommend running the game text through a word document for spelling and grammar checks before you add it to the game. I caught the word "exige" in the personality train help guide under "Clean", which I think is Spanish, and a few other spelling/grammar mistakes in random areas.
- When talking to characters, they'll say something like "we have no interests in common". What counts as a "shared interest"? If you maximize both of all characters' interests or even just 2 to 5 interests, you still get "we have no interests in common".
- Phone calls seem to be automatic after a certain amount of time has passed, or possibly when a character is feeling needy. If you get the phone numbers of 5 characters on the same day, then they will call around the same time. I think whether a character is socially or sexually needy should randomly increase or decrease when you're not interacting with the character. This will make phone calls more random and spread out, AND more frequent at the same time. Personality traits should factor in this as well.
- Who initiates hugs, kisses, and flirting shouldn't really increase/decrease Submission. Slapping Ass and maybe Chest Touching should, but not the others. Those are simple gestures of affection and shouldn't change who the dominant is in the relationship.
- I think gifting Items should increase Friendship. Most of the time, you're giving them 2 or 3 items to make them less tired or more healthy; that's an investment. It would just make more sense that the NPC would grow closer to you.
- Catching someone masturbating in a bush at the beach still counts as "opening a door" on them. Since they're doing it in public, I would come up with a whole new interaction for this event. Or just default it all to the "Oh! You caught me."
- Personal Questions or Sexual Questions should increase arousal in the player and NPC, unless a personal trait like Demure or something like that.
- Allow NPCs to approach you. If you're not talking to someone and they are feeling needy, let them randomly initiate conversation.
- Side Note: If you're not working on it already, I would add a "Preference System" for the NPCs. Maybe they prefer tall people or short people, Thin or fat, lighter skin, or dark skin, etc.
- You're probably also working on this, but I would add more things to do, specifically on the Weekends. I would look into adding Minigames. Maybe an Arcade building or a DDR Keyboard minigame at the nightclub.
I have more things I can recommend, but this post is getting long. You have an amazing game here, especially being built from the Ren'Py engine, you should be proud! I look forward to playing this game and maybe even supporting it financially in the future!