Bf & coworker

My bf of almost 4 years wants to go have a drink with one of my coworkers because they’re “friends”. Mind you, they don’t know anything about each other but “that’s the reason to go. To get to know each other”. She’s the one who said about it on his 21st. They’re social media friends, talk once in a blue moon & only talk in person if he comes into my work even that’s limited.

What do y’all think? Let him go or too sketchy?