Sexual comments at work by straight women

I was wondering how you're usually dealing, with these kind of comments that are considered OK by some because you aren't sexually attracted to the gender.

Context: I work as a nurse, which has mostly female workers (here in Québec at least). I was minding my own business at work fetching some locked away material in my boss's office and these coworkers (women) passed by my office and started asking me about if my dick goes to the right or left in my pants and that it would be enjoyable for them for me to wear tighter pants so I'd have a dick print for them to look at. I usually just laugh and ignored it, but yesterday it was more intense than usual and made me feel quite uncomfortable. I tried telling them but they just ignored me and laugh. I am a bit disappointed in my boss that was present during the conversation for not telling them that it wasnt appropriate.

Thing is, I feel like that if it was the other way around (me telling them sexual comments), even though I'm gay I would have a disciplinary warning because I would be sexually harassing my female coworker.

Feels good to get this off my chest. Also, sorry for grammatical errors. French is my first language.