G.A.T.S.
Much like the famous (and annoying) acronym H.A.G.S., G.A.T.S. is written in yearbooks. Although instead of Have.A.Great.Summer it means Get.Ass.This.Summer.
Natalie: Hey sign my yearbook!
Teresa: Okay. -writes G.A.T.S.-
Natalie: Thanks, I will!
Teresa: Okay. -writes G.A.T.S.-
Natalie: Thanks, I will!