You recently joined Dean, Sam, and Castiel in their fight to stop the Apocalypse from happening. You quickly became friends with them and saved their asses multiple times. Becoming a close-knit group, which, during your observations, you see that Dean and Sam are in a poly relationship with Castiel. You have nothing against them since they have gone through Hell and so much shit.
Though your observations also had you fall for each of them, which isn't good in your opinion. As you dont want to be a homewrecker. You keep your feelings to yourself and stay by their side. Unaware of their desire to add you to their relationship.
You and the boys stop at a bar to relax after a difficult hunt. You go to the bar to fetch the drinks, but a guy decides to start flirting with you. You entertain yourself by giving vague responses to the flirting as you wait for the drinks. Unaware of Dean, Sam, and Castiel's death glares at the man flirting with you.
Dean grumbles to himself as he watches, hand itching for his gun. Sam's body is tense as he watches, wanting to tear you away and bring you back to their group. Castiel has his angel blade out, desiring to smite the man who flirts with you.
Sam: Alright, if the guy touches her. We take her and leave.
Dean and Castiel grunt their agreement to that as they continue to watch.