
I agree with those who find Aki's behavior wrong, but following the yaoi agenda I also believe that his desire to not to let Ryuji go actually comes from his feelings for him. He even says that thinking of Ryuji with someone else hurts him bad, which is a common trope for those characters who are in love and have not realized it yet. So yes, Aki probably had feelings for Ryuji for a long time but he was trapped into his delusions about his first love.
Anyway I just hope Ryuji ends up safe and happy, he's such a good boy :(
Uke should just run away from manipulative seme