Yeah, I've gone into them and commented everything under the sun and gotten nowhere before? But it all really depends on how clique-y everyone is and how open they are to "new faces". He's gonna be late 20s~Early 30s. Is there older PBs around for him to not feel ancient all on his own? Haha.
Organic is also fine. Sometimes just commenting and giving each other shit can build a relationship. So doesn't have to be some major huge thing all plotted out. Can be a thing where they got talking over a tat, or talking trash about someone who was being blatantly gross at a bar about her or something that bonded them together and just go from there.