Well, I put in garbage, just to see what would happen.
You'll get stuff like "I can't believe we're fucking in our uhdsiouhsduhfsd's bedroom even though we're ididsjisdjijsdff and 20ee0k20dwwdko!" and "I'm going to cum from my dsiofdiojjidsfdfs's giant cock!".
So silly.
Even if you put in "roommate", it's silly. It's clearly written for a certain sort of taboo relationship and there is no effort to hide that in the dialog. Whatever you put in, they're exasperated that they're doing the sex with it. "No we can't have sex, you're my green grocer! Oh well, put your big cock in me I'm horny for my little green grocer who I grew up with in the same house." And don't get me started on "Our little insurance salesman is all grown up".
Oh, the renders are amazing and the animations are amazing. This is top notch entertainment from Inceton. I wish there was more actual game play for a game that doesn't have a VN tag. The options are mostly just story forks.