Alright, so obviously the game is still in the very earliest stages of setting up the plot, characters and world. Trying to guess at where the story is going, to make a suitable name, is maybe a bit silly, but hey. I'll lay out what I expect the story to be based on this initial release, so you understand where I'm coming from.
Firstly, the protagonist is currently undeveloped. Not in the 'coming of age' sense, but in that there is almost no backstory. I assume, based on the planned tags, that this will change. One or more characters from the protagonist's past will become a part of the story, most likely after his character has become more assertive. They will be impressed enough by this to set aside the shackles of social conditioning and take up the furry handcuffs of inappropriate sex.
The opening scene could be one of two things.
1) Deborah will use the protagonist as a tool to 'work through issues' that one of her client couples has. The guy who walks in on them is a cuckold, and the whole thing was set up as a roleplay to help improve the relationship of the cheating woman and the angry guy.
2) Deborah will see that the protagonist is insecure and help him overcome his confidence issues by inviting him, after a bunch of foreplay, to have sex with one of her sex addict clients.
The protagonist will meet a bunch of girls at SLU, including Anna and the girls staying with Deb. He will initially have issues with bullying, because that flashback to childhood has to be going somewhere. Word will get back to Deborah via one of her tenants, and she'll use the power of sex to pound manliness into him, stopping the abuse.
Eventually the protagonist will party at Amandit, where he will meet the model lady. There will be some antagonistic force involved in their relationship, a boyfriend, or a manager, a criminal or something. The protagonist will have to use his developing manliness to protect the hot model girl and win her heart.
So there's a good chance the game will heavily feature the protagonist sexing up women who are in a relationship already. I mean it's already happened twice in the first release, once in a flash-forward and one in the fancy apartment (assuming the housewife character is actually a wife).
So my name suggestions are;
Top Class - 'Top' as a euphemism for dominant sexual partner. Deborah is teaching the protag to be a top. The story will eventually have an element of upper class involved with the model girl and Amandit. Also it's a college story. This name seems appropriate but is maybe not that nice aesthetically.
The Big Time - Big with a triple meaning. The euphemism, alluding to the 'coming of age' aspect, and the assumed high society plot with the model girl.
Hard Graded - Sounds sort of similar to 'r-rated', it has hard in the title, and the grade thing again alludes to the college story. It sounds good in my head but I think it's probably not a great name.
By the way, the models, animations, general presentation of this VN is excellent. It badly, badly needs to be proof-read, the English is quite terrible. Almost every text box has grammatical or spelling errors. You even spelled coffee correctly twice, then incorrectly immediately after. If it can be proof-read and localized this would easily be one of the best VNs.