"What's gotten into him?" Lupin demands as the Gryffindors make their way to Astronomy. Black basically scampers up to the tower. "Something strange must've happened at Hagrid's hut!"
"Maybe he's in love," Pettigrew suggests, looking to James for agreement. James is clearly disinterested. Lily stifles a laugh, a break from listening to Mary and Marlene quiz each other on last class, somehow turning into a lecture on not judging a prospective boyfriend based purely on looks.
"Peter, have you met him?" Lupin kindly points out. "No, I'd say he's been a bit secretive."
"Maybe he's fancied Evans longer than we think," Potter fumes. "I'll be sure to beat him in that Muggle fight! Evans probably needs proof of my agility and my upper as well as lower body-"
Lily turns to Lupin, Pettigrew, and Potter. "Being in love and fancying someone are the same thing!"
"You would know, won't you, Evans?" Potter snaps. "Have you seen him naked too?"
"I told you, I accidentally walked in and clearly regret it to this day!" Lupin whispers. "Believe me, we aren't in love!" Somewhere along their years at Hogwarts, their classmates joked about Black and Lupin being and old married couple. Now, they joke about them being just a couple. It has gone too far.
"I should've chosen a different threat," Lily mutters. She snickers and walks off to the Astronomy tower by herself.