Seems pretty similar relationship to me, Sanae being a good girl and worried, Kanako being the victim, and Suwako trolling, unless im missing the joke
Kanako-sama!!E-eh.I see. There are already Kanako and Sanae.UUAAAAAHHBi-te!It'd be nice if they're having good relationship like us!Sanae...So all three of us have gathered!