I'm mean, he himself said (if I'm not wrong) that all he remembered before getting into hikaru's body is the feeling of loneliness, so i guess we can assume that he did had emotions, he just didn't had it's concept, how to react to them and what were them. I guess he only came to know that because he now has hikaru's memories and that he came to like Yoshiki because he accepted him and 'ended' with his loneliness
(づ￣ ³￣)づ
by his memories, i mean the concept and how to perceive emotions.
He has some of hikarus memories and emotions but he cant feel them the same as humans, the entity itself says he cannot feel love or attraction the way yoshiki does
maybe i'm not normal or whatever, but i hope "hikaru" can get his happy ending, i refuse to believe the emotions he has are because he is in hikaru's body, i want to believe all that emotions, happy, sad, angry, disappointed, jealous, and love..they all belong to that monster feelings.. I know if he could make a wish, "Hikaru" would want to be human..