Starla 
Although I refer to Starla and Roy as boyfriend and girlfriend their relationship was always much more casual and open. They both cared deeply for each other and seemed to click on every level, but neither was able to take that next step and ask "what are we?" But you know what? It worked. They were both happy with what they had, they're young! They didn't need lables. It's when Star got pregnant that things changed and Roy finally decided that he did want to commit fully. Unfortunately, Star wasn't sure if she felt the same way, and then to make matters worse she died and became a vampire. Roy would have liked to still be one big happy family but the vampirism put a wrench in that. Not to mention Starla's other boyfriend is still around.
Desmond 
Roy's pride and joy! He loves his son so much and he loves the person that Desmond grew up to be. He always wanted to instill in Desmond that humanity has value and to honor both his human and vampire halves and he believes that Desmond grew up to be a person who does just that. He is also proud that Desmond dresses and expresses himself how he wants, even though there are some things Roy doesn't quite understand (like hyperpop), it makes him feel like he did everything right as a dad.
Amadeus 
Roy hates this man. Although he loves Desmond and wouldn't change a thing about him he still blames Amadeus for ruining what could have been his chance for a normal family. On top of that, he constantly feels like Amadeus is trying steal Desmond away from him and take over as his father...which he is. Roy feels powerless in the situation as well because whithout Amadeus' financial support he would be struggling to take care of Desmond and although he would never admit it, he needs Amadeus' help whenever it comes to Desmond's vampire side. And that's not to mention the fact that Amadeus could kill Roy at any moment too, which makes him literally powerless. At the very least Roy is aware that Amedeus won't act out of fear of Starla and Desmond turning against him and will take advantage of Amadeus where can, like sleeping on Amadeus' couch and stealing money from him to pay for his car insurance.
Ximena 
Ximena is the one who made the final decision to let Roy into the band and although they have good chemistry on stage, in their personal lives their relationship can be rather tense. Roy likes Ximena and considers her one of his closest friends, but her blunt and cold personality makes it hard for him to truly connect with her. Oddly enough though, it was one of those blunt conversations where she told him he should never be a father that made him reconsider his situation with Starla. So, without her he probably wouldn't have the son that he loves so much today.
Styx 
Styx is the one who initially found Roy and convinced Ximena to let him audition for the band
