The female colleague doesn't get expanded, which is good because she's not relevant enough but that's not the usual norm to be honest.
And further down the story the main female gets in a group date, a dude tryna get her drunk and hook up but main male stops her, well surprise surprise it's because the dude tryna get her drunk is MC's brother
And after MC told his brother to fuck off, he was never heard again.
And not to mention the FMC's little sister is seen only once.
Honestly those are irrelevant characters in the story. But that might have just been me who wants others to get in the main plot