He got jealous

You and Heeseung are together since highschool and you guys really know each other.While you guys were cuddling in bed at each other, Heeseung have your phone while you were just nuzzling your head towards his neck.He then let out a deep sigh and you pulled away a bit and look at him."What's wrong?" You asked and he then show you that a random guy just texted you.He look at you like he was having a death glare