She's not identifiable enough to tag, but the artist says the redhead on the left is Hatori Chise from Mahou Tsukai no Yome.

Is this a parody of something?

Live2Run said:

Is this a parody of something?

It’s a reference to a scene from the ping pong animation, where one of the characters (Kong Wenge) sings ‘Hitori Bocchi no Christmas Eve’. You can see here at 1:02 https://youtu.be/8i93vXUKqnI?si=B0JyPaPttL5HXSrA

cool art of all them

i dont see why konata would be a "femcel"...she has friends...she has a normal life...

Recognized all of them aside from Chise and the other Bocchi.