Today's themeless is held together by a standout pair of 15s. FRESHMAN FIFTEEN in particular is the kind of fun, lively entry I love seeing in themelesses! Grid-spanners often put major constraints on how much liveliness you can work into the rest of the fill. Claire was smart to section off her four corners—that way, she didn't have to deal with letters locked in by the 15s and letters locked in by the other corners. She was thus able to squeeze in gems like ARS POETICA, TANNIC ACID, and BELIEBER. Claire's LAST LETTER clue was also much friendlier than the one you see. You're welcome ;).