The answer is: ingroup, outgroup
In sociology, individuals would perceive an ingroup as a social circle In which they've become a direct member.
An outgroup on the other hand would be a social group that they interact with but they've never been considered as a direct member of that social group;.
Danny and Andrew are both in the filmmaker's club. This mean that for Andrew, filmmaker's club is an ingroup because he is a direct member of that group.
Andrew only interact with the fraternity because of Danny's invitation. So even though he interact with that social group, Andrew has never became a direct member of the fraternity. Which might explain his awkwardness.