to commit a heinous crime (see Molina); seems to refer to homosexuality
IPAspelling:
kwilontiɑ
Alonso de Molina:
cuilontia. nite. (pret. onitecuilonti.) cometer pecado nefando. Alonso de Molina, Vocabulario en lengua castellana y mexicana y mexicana y castellana, 1571, part 2, Nahuatl to Spanish, f. 26v. col. 2. Thanks to Joe Campbell for providing the transcription.