When Quinn got home on Monday, Rachel was yelling about "going Lima Heights" while Santana tried to calmly negotiate whatever fight they were having. The blonde decided confusion was better than interceding at that point, and made her way upstairs to change.
Tuesday, she came home to find her girlfriends on the couch, with the credits of a movie rolling. Santana had her laptop up and was diligently trying to explain the plot of The Departed with a Powerpoint presentation and a series of flowcharts.
Wednesday, while she was cooking dinner, Santana came over and gave her a kiss on the cheek. She offered to help while Rachel just yelled, "Where's my meat, woman?" Quinn highly suspected that the "bacon" Rachel consumed was still a vegan substitute.
Thursday, Quinn was actually afraid of what she'd find. She'd considered sneaking in through the fire escape, but that would probably set off one of the alarms. She pushed the door open and found Santana and Rachel on the couch again. This time there were two bottles of wine open on the coffee table. Both were empty. Santana was snuggled happily against Rachel, and Rachel was sobbing and mumbling about how "she just has so many feelings!"
Friday, Quinn entered the apartment, only to have Rachel pounce on her. What the hell? This was entering the way too good to be true stage of insanity. Rachel was never like this in bed—or against the door, as they were currently. Quinn vaguely registered Santana chuckling and lighting candles as Rachel did her best to win the record for Fastest Stripping of Quinn's Clothes. Quinn knew she should just go with it…that she was looking a gift horse in the mouth…still, she was way too confused to actually enjoy it.
"Did you two get struck by lightning on Monday or something?" she gasped.
"I'm sure I don't know what you mean, Quinn," Santana said, giving her a soft kiss.
"You're…ungh….You're acting like each other!" she managed to say through Rachel's increasingly aggressive kisses.
"Want to fuck us back to normal?" Rachel asked.
It took exactly two seconds for Quinn to approve this plan.
"Drama class," Rachel mumbled sleepily a few hours later.
"Hmmm?" Quinn asked.
"Drama class," Santana repeated. "NYU collaborated with NYADA for a special guest lecturer. Our homework was to swap personalities with someone for a week."
"Mystery solved," Quinn said, smiling. "Now I'm going to pick up some Chinese food. You two behave while I'm gone."
"We always do," they said in unison.