I always like making the various shirt designs in Leftover Soup - primarily, the ones Max wears. I actually did make Simon's "Veni Ad Me Frat" shirt available, but I don't think it ever sold too many. T-shirts used to be the primary income stream in early webcomic days before Patreon, but that market has dried up a tad. These days, there are plenty of companies you can just get custom shirts from whenever you want, so if you want something with a non-copyrighted slogan or saying on it, you can just go get it. I recently bought a shirt with "Warrior/Poet/Philosopher/King" on it, and all it needed was two minutes' worth of picking out fonts and about twenty bucks.

Anyway, I do think the whole "sexy clothing does not equal asking for it" thing has been well-established at this point, and the only people who would still quibble about it are the sorts who think their boners trump other people's autonomy and will argue any point in bad faith to make that happen. That being said, though, I do think that in certain pre-determined circumstances, one can use specific articles of clothing to send a message, and certain types of consent can be such a message. That's more of a BDSM-scene kinda thing, though, not really something that applies on the street or in a night club.

Which is to say, regardless of Max's opinion on the matter, if you ever do see someone wearing a shirt that says "YES I WANT YOU TO TOUCH MY BUTT" I would still recommend asking for verbal clarification before touching the butt in question.