You're not wrong, as far as the game in its current state, that it looks like that. But the reason is actual far less interesting and more practical. While there is currently (and will be in the future) a lot of IR content, it is not exclusively an IR fetish game. I describe future plans below.
The way that I am coding the game uses components that come together with conditional statements. (Lessons from a lot of trial & error in 3+ years of experience working on my other "main" game.) Since the apartment is the central location, this first release includes the "roots" that will allow all of the necessary growth as the game continues to develop.
While there are going to be short scenes with other visitors to the apartment, Brian is the only person who will ever come to live with them for an extended period of time. He is the only character who needs to have the ability to move around freely and allow the two protagonists to move around freely while he's there. Code-wise, it makes sense to build all of this at the beginning before things get too crowded. Story-wise, it makes sense for a couple starting in this lifestyle to look close to them relatively early in their exploration. (He's not intended to be "the first," and once I have more content, the start of his week will be pushed back slightly.) Writing-wise, the MC's character didn't *have* to be black, but that is easiest for me to write as I am trying to get more comfortable with writing in this genre. (The writer for my first game recently left for personal reasons and I am taking over writing duties.)
So, I'll tip my hand with a couple of spoilers for future potential LIs for the wife. Fans of my other game will be happy as well:
And lest anyone be worried that the husband will not have any "options," there are currently two in the game, and others will be introduced. There will be fewer for him due to most of the paths being more focused on the wife. Also, he's not a particularly outstanding dude so he just doesn't have nearly as many options as his hot wife, realistically:
Beyond these named story-centric LIs, there are also going to be a handful of possible brief LIs for both husband and wife. Something akin to the masseuse, just a quick hookup but no real character development.
Hope that helps to explain where things are headed.