Yes, Matthew did use a sedative to keep Jin from leaving, but it wasn’t intentional. Calling it 'rape' seems a bit extreme cus, before Matthew used the drug, he and Jin were already having consensual sex. Jin only got upset because he thought Matthew was using the same drug that Brandon had given him, not because he felt violated. Matthew would never do that without Jin’s consent.
If you know Jin, you wouldn’t say that because the only way Matthew can keep him in his studio is either by tying him up or making him unconscious. Yes, Matthew's decision wasn't the best choice, but he was desperate. I'm not trying to defend him, I'm just trying to explain the character and why he acts that way.
I hate that the author made Mathew drug him and rape him it just doesn’t seem like something Mathew would even do:(