I don’t really swear in my cartoons.
I’ve very very occasionally used mild language, but in my experience if you have to use profanity to sell a joke, the joke wasn’t that good to begin with.
I have to admit, I struggled with this cartoon a bit. “Damn” isn’t really swearing by most accounts, but you’d be surprised by some of the complaints I get.
I did consider “darn,” “rats,” and “crap” for this, but there’s just something about “damn” that punctuates this nicely. So it stuck. Complaints be damned.