Zachary is his roommate and definitely a kindred spirit in terms of throwing wealth around. He would feel very comfortable around Dominic for that reason - but it's up to you how Dominic would react to him, since he's...you know....eccentric. So possibly friends, possibly another dormmate who thinks he's a silly, weak child who is amusing when he throws fits. Up to you!
Orna is a possible enemy because she thinks Rita Skeeter is an absolutely deplorable figure and everything that's wrong with modern journalism. So if her son seemed to have the same pride and attitude, that probably wouldn't go over well. She was super super enemies with the prior Dominic Skeeter. But again, it's up to you!
Dorian doesn't know him....and wouldn't like him if he did, being very judgmental about Slytherins.
Nora likes him - another of her brother's pretty friends and roommates! She probably finds him amusing and entertaining.
Finally, Skye. I don't really know! She would know him vaguely from the house and by reputation - probably is hoping he'll settle down at some point with a steady girlfriend, like she does with everybody, but is wildly entertained by his antics and exploits. What do you think?