Social group at skid row Oxford met occasionally in clothes store (9)

I haven't cracked this one yet — but the brilliant team at Fifteensquared have:

Social group at skid row, Oxford met occasionally in clothes store <so> C <ia> L <gr> O <up> A <t s> K <id> R <ow> O <xf> O <rd> M <et>; “occasionally” means every third letter only is used, here throughout the whole of the wordplay part of the clue!