I think the poster was referencing Jesse's earlier girlfriend Jane from Season 2. When Walt breaks into their apartment to recover some money, he sees Jesse and Jane in bed after a hereion binge. Walt notices as he is leaving that Jane is choking on her own vomit, but chooses not to save her.
That was another horrible scene
Most people don’t realize that when people die from ‘an overdose of drugs’, that is usually how it happens
You are unconcious, and your body tries to get rid of the drugs, and you choke on your own vomit.