Her Valentine's card was even sloppier this year, filled with exaggerated sweet talk.

sloppier 是形容词 sloppy 的比较级形式。sloppy 本意是"马虎的、邋遢的"，在这里引申为"肉麻的、过分甜腻的"。 sloppier 表示"更加肉麻/更加甜腻"，通过比较级形式强调程度比往年更甚。