Ooooooo your bf gets jelly jelly
Steve would freak out when he'd see someone hitting on you. He doesn't like it, you don't like it, no one likes it. When you're uncomfortable, Steve is uncomfortable. So he steps in saying, "I don't think the lady likes that." The guy would back off. If not, Steve would lead you away. He doesn't want to cause any trouble.
Tony would get all flustered. Why would someone hit on his girl?! Everyone knows she's taken! Tony would march up to the guy and yell, "Leave her alone! She already has a boyfriend, which is me!" The guy would back off. If not, Tony would punch him, but you drag him away before the trouble starts.
Thor wouldn't understand why someone would flirt with you. You're taken. Thor would walk over and ask, "What's going on?" You would grab his arm and say, "He's my boyfriend, man." If the guy wouldn't back off then, Thor would firmly tell him to back off and stay away.
Clint would march over there and grab the guys collar, telling him threatening things. You would just smile, you knew Clint wouldn't hurt him. He was your knight in shining armor. If the guy wouldn't back off, Clint would shove him away and yell at him.
Poor Bruce would be sad. He would walk over and nudge you, and you'd grab his hand. "Sorry I'm taken," you say, and the guys would usually back off. If not, Bruce would tell them politely to leave.
She'd kick them.
He'd loom over the guy, his glare extremely menacing. The guy would get so scared he'd almost pee his pants. If he didn't back off, Loki would bop them in the nose. Then he'd ask you if you were alright.
He'd sigh and lead you away. It usually works most of the time. If the guy was persistent, though, Bucky would shove him away and get in a fight that would last only a few minutes. Bucky is that strong.
He'd roll his eyes, sigh, pick you up and zoom away. It always works.
She'd politely ask them to leave you alone. If the guy was persistent, she would say, "She's not interested in guys." and call him names. If he was STILL persistent, she would use her powers to make him leave.
He would glare at the guy, making them step back. T'Challa always had a way of scaring others. He would tell them to leave and if not, he would hurt them really, really bad. (lol Joker)
Double update you're welcome children
This preference was requested.