I think i can clear this up for you as best as is can:
1- Sousuke in a way likes Iroi but it is not love. The "love" hes trying to portray to Iroi is the possessive "your mine and no one can have you but i wont be in a relationship with you because i don't want the hassle".
2- While he may seem emotionless it is hi way of hiding his tru feelings which again goes back to being possessive but not willing to be in a relationship.
Also Iroi is at fault because while he knows Sousuke doesn't want to "be" with him he still has hi contact because deep down he cares for him and cant let go BUT he is trying to cuz he met someone who will be open with him and "love",possibly, him. ANYWAY long story short Sousuke is a ass who wants to keep Iroi under him(pun intended) and Iroi cant stand up for himself but wants Hakouto to love him. I hope this clears some things if not please ask and ill answer as best as i can (=・ω・=)S
i never said he actually loved him but he is giving Iori a sense of false hope that he feels something for him but in reality its nothing but possessiveness. Kinda like "this is my plaything and no one can have it or else". Rape is bad yes but Iori wasnt putting up much of a fight, mostly because he cant he still holds feelings for Sousuke but those feelings are slowly diminishing the more time he spends with Hokouto, which is why he was so upset when Hokouto saw him with Sousuke.
I think he just wanted to have his cake and eat it. His "toy" was moving on and getting what he was looking for elsewhere so he wanted to ruin it to keep his as his side piece.
i swear i cant understand sosouske like if he really loves Iroi he sure has a werid way of showing it and to top that of sosouske is practically emotionless so i cant figure it out from there if he really did love Iroi that would give him a little justification but i really don't think he does