a clemtaco is a fart manuever where a person farts in an open book/folder/binder or any thing that opens on a fulcrum (a V shaped opening), and then pulls the sides to create a strong push of air causing a fart to accuratly enter the victim's nasal cavity causing the smell to go deep inside the victim. Causes nausea.
clemtaco-er: *farts in a book*
victim: ... please don't
clemtaco-er: *pulls sides*
victim: OH, COMON *gag*
"So I was hanging out with my girlfriend and I clemtaco'd her, she got sick and threw up on me"