Centurians? You mean Hyuzefians? There are Hyuzefians, Chironians and Kolniks who will be more prominent in the final week. And if you are not into the Hyuzefians the best you can do is the SFW version. There you will only date 3 but there is no explicit sex. I was going to make it more like a dating sim but the story kind of required them. and adding entirely extra branches does not interest me and would take extra months to do so.