Despite being easily irritated, Trevor has a good sense of humor, and says in an e-mail to Jimmy De Santa he (Trevor) loves him. He may be the most frightening person in all of San Andreas, but if you treat him with respect, he will be nice to you back.
He or Michael can be killed in GTA V. Many players prefer to kill Trevor instead as a way to avenge the death of Johnny Klebitz.
Trevor had actually foreshadowed his own determinant death in previous missions in GTA V and in GTA V Online.
In one of his dialogues when talking to a random pedestrian or when driving a vehicle and flipping off a random driver, he may say "Why hasn't someone sensible shot you yet?". If the player chooses to kill Trevor as their last mission, the name of this mission is called "Something Sensible".
If the player fails to inject Kerimov with the adrenaline shot after he dies from being tortured by Trevor, a unique "Mission Failed" cutscene will play where Steve Haines will notice that Kerimov had now died completely, and after an argument with Trevor, he will say "Because soon, I'll put an end to your little charade..." before he leaves. This is a hint and foreshadowing of Steve's view of Trevor as a liability and thus was the reason he ordered Franklin to kill him, deeming him as well as being too "uncontrollable" and "insane".
In the Series A heist in Online, when the Online Protagonist and his crew are about to leave with the Tanker filled with Meth, he will warn the player that they should not let the O'Neil Brothers shoot it too much as it is really flammable, but will brush it off later by saying "But, hey, it's your flaming carcass, not mine.", foreshadowing his death in "Something Sensible".