Sässy is another Name for Sexy, it doesn't mean exactly how Sexy he or she is.
Sässy is the smaller version of Sexy, so that you don't come across as an dirty Guy or Girl.
"You're Looking Sässy (Good) Today"
"Girl you're looking so Sässy Tonight 🥵"
"I met this Guy Today and he was so Sässy 😩"