This creepypasta is called "Mind Games Mod: Bad Ending" and belongs to the Psychic, who went berserk from the drug and killed the Boyfriend with a shot.

Full story:

Following the events of Mind Games Mod, Psychic went to his bedroom, where he sat on the floor and thought in shock about what would happen to him next. He even cried when he thought! Suddenly, he heard some voices ordering the Psychic to inject the drug, like Suicide Mouse. He, following schizophrenia, took a syringe from the shelf, and the mist in tears injected the drug. From this, the Psychic felt much worse, his eyes turned pink, foam came from his mouth, and... Psychic went crazy from the drug...

Meanwhile, exhausted Boyfriend was cleaning up the pieces and debris in the fireplace room, when suddenly he teleported into the void. He saw the Psychic in front of him, but with changes: foam came from the mouth of the fog, his eyes were completely pink, fury in his eyes. The rapper did not know that the Psychic had gone berserk because of him, and began a rap battle with him, unaware of the danger awaiting him. Because of the Boyfriend, the Psychic became even more brutalized, chained the rapper in pink chains and told him that he had enough strong fight, and also told the rapper that if he started a rap battle with him, he would kill him. It would seem that Boyfriend should have surrendered, but no: he continued to fight with the Psychic until the very end, until he dies from a gunshot: The Psychic can not stand this nightmare and kills the rapper by shooting his brain with a gun. Boyfriend dies, Psychic faints from insanity...

...Psychic woke up in his bed and found out that he had a dream where he kills Boyfriend. His dream was true: Boyfriend really died. Since then, he no longer disturbed the Psychic....

The end.