I
His father abandoned him, after it was discovered that he had a sexual relationship with a suspect. All his success wasn't aknowledged and he got told by his father to admit his fault in disappearance of drugs. Imo, his father wants to get rid of him, that's why he is leaving small 'gifts' for him, that are those drugs. In the end he is addicted to them (worn out look, thin and falling out nails). Miguel knows it, wants him to 'release' from his addiction and his 'connection' to his father, but can't. Well that's what I at least understood...
Even if miguel couldn't kill him coz he loves him so much, in his condition like this, jake will die slowly due to overdose. And let's curse that damn father who did that to him. That father is the real evil here.
Ah, I didn't notice the drug thing. I dunno why, you can even see the syringe on the counter. But what was Miguel doing for Jake when he handed him that paper and was talking about Amsterdam?
(⊙…⊙ ) And then.. What happened in the end? I got confused.. Can someone pls shed the light?