He goes to classes to see Byleth in her new outfit.

Sylvain woke up in the morning, sitting up and stretching. "Wow, I slept great!" he remarked as Mercedes also woke up, rubbing some light sleep out of her eyes.

"As did I," she smiled warmly. "Professor Byleth has more classes for the Blue Lions today, but it's supposed to be a shorter period, then we're free the rest of the day."

"Right, best get moving then," Sylvain grinned, getting up and they quickly bathed, together of course, before getting dressed and hurrying through Garreg Mach to Byleth's class. Taking their seats, Sylvain looked around, before seeing Byleth come in, dressed in a slightly skimpier dress than the armor she had been wearing. It was still black, but Sylvain figured that this complimented her well. It was also cut just low enough to expose some cleavage, though unfortunately not nearly as much as Manuela. Shame. Still, it also had a nice slit along the leg. Yep, the entry to have Byleth dress sexier for class definitely worked.

(It's Byleth's Dancer outfit for reference.)

The door opened, and a harried looking Annette rushed in. "Sorry I'm late Professor, I oversl- AH!" she yelped, tripping, and falling ass over teakettle, her books hitting the ground. There was some amusement amongst the class, mixed with some concern, even as Byleth moved to help Annette up.

"It's quite alright Annette, I would prefer if you didn't rush so much next time this happens," Byleth stated. "It's a good way to fall."

"Er, ah, yes Professor, I understand!" Annette inclined her head, before rushing to her seat.