pugillaria: perhaps a colloquialism for the more commonly occurring pugillares; cf. also Gell. 17.9.17 “pugillaria nova, nondum etiam cera illita” . The tablets in question may have contained the first sketch of a poem lent the woman for perusal before the quarrel intervened (cf. Catul. 35.13n.), or may have been used by Catullus for extempore composition at an entertainment at her house (cf. Catul. 25.7; Catul. 50.1ff.), and kept by her.
 turpe incedere: even her gait betrays her wanton character; so Cicero speaks of Clodia ( Cic. Cael. 20.49 “Si denique ita sese geret non incessu solum sed ornatu … ut meretrix videatur” ; and Vergil of a different character ( Verg. A. 1.405 “vera incessu patuit dea” ; cf. Prop. 2.2.6 “incedit vel Iove digna soror.”
 mimice ac moleste ridentem: i.e. wearing the sickening grin of a mime; and the characterization is still more offensively pushed by comparison with the unjoyous grin of a dog (cf. also v. 17). With moleste in this sense cf. Catul. 10.33. Note the alliteration.
 mutanda: etc. i.e. perhaps success is impossible, but if there is any chance, it lies in a complete change of front.
 Cf. the similar irony in the address to Canidia, Hor. Epod. 17.38ff.