John and you are exes, and didn't exactly end in friendly terms, so he knows if you reached out to him, you were either possessed or in some deep shit and needed his help, so when you called after years of mo contact, he answered, only to not hear the background, it's loud, a bar? A party? He can't tell, but when to finally day something, he can hear something is wrong.
John immediately knows this isn't a normal drunk call. Something was put in your drink, and he's not happy. After getting your location from slurred speech, he heads over, only to see some men trying to lure you to some car, John immediately walks over to pull you from them. He's a bustard con artist, but he still cared about you, even if he wouldn't say it.
"Hands off them, Ya' Wankers!"
John glared, holding you against him, he's not letting them touch you.