The fact that you made this in just two months and it's already better than most titles in the 3D NTR genre is genuinely impressive. With more polish and content, this could become one of those games NTR fans mention in every discussion.
Some of my personal recommendations:
1. More characters.
As others have said, more people would benefit this greatly. One of the stream options is an old bully. Have him fall for our childhood friend. Stalkers, Pushy IRL fans, another childhood friend? Even if they don't have full routes like the landlord, having more miscellaneous events would go a long way.
2. More control over influence.
We can almost egg on the Landlord to try and take our childhood friend. With the messaging system I would love it if we could either steer her into his (or others) arms, or simply make them think she is interested, leading to them thinking she is playing hard to get and get pushy. What really sold this for me was the Landlord mast scene. If you simply go along and agree he says something along the lines of "You're not very protective of her." That could be the perfect flag for him to start moving on her without needing a missed payment and start us having to fight over her attention while also helping her stream.
3. New locations and date maps.
Combining ideas from points 1 and 4, what about new places to take her like bars where she could get too drunk, alleys where you might run into thugs, or simply different places to spot her out with someone else? Even VN-style date events would be great. These could build or break your bond, win favor with others, or push NTR opportunities.
4. Build the emotional bond.
NTR hits hardest when there’s a real connection to the girl. Movie nights at her place to talk, reminiscing on old times, more dates, subtly pushing her into others arms through talk. These could be used to either deepen the relationship or subtly push her away depending on your choices. Let me care about this girl before I lose her.
5. Lewd Stream/Record.
Would love to see her slowly convinced either by us or her fans to do more suggestive streams. Start light: yoga, poolside, or onsen content. Then slowly escalate. Eventually, let us produce porn videos and run a separate site for it. Choose positions, people, setting, etc.
6. Pregnancy.
I know. But I would love an actual mechanic to this later on. This is mostly a personal wish and not really needed for the game to thrive.
I wish you the absolute best and I’ll definitely be supporting this and any other projects you make.