Played with in "The Wreck of the Hesperus". The skipper's daughter sits down, revealing the long Victorian pantalettes under her dress - not very sexy to a 20th-century viewer but likely scandalous at the time the poem takes place. Then, when the narrator reads the "And her bosom white as the hawthorn buds/That ope in the month of May" - which is taken directly from Longfellow's original poem - she is shown covering her bosom with her hand. One way or another, the "bosom" part is cut from at least one release.
In "Law and Order", the Catnip Gang lure mice to be made into popsicles using a mutoscope of a mouse woman in a form-fitting garment doing a provocative dance.
Mighty Mouse: The New Adventures
In "Witch Tricks", when the witch reacts to Scrappy taking her tooth by convulsing, you can see that she's not wearing underwear under her nightgown.
A disputed example, but so many people have interpreted Mighty Mouse smelling and inhaling the crushed remains of Polly Pineblossom's flower in "The Littlest Tramp" as an allusion to cocaine abuse that the show actually got in trouble for it. The scene was cut in reruns to avoid more controversy, but most versions available now have the scene uncut.
"The League of Super-Rodents" has a couple of questionable scenes involving Madame Marsupial. She distracts Mighty Mouse on a dinner date and seems pretty excited about Mighty saying that he's sorry if he's too forward with the request he's about to make, even if it turns out that he wants another helping of spaghetti rather than anything risqué. At the end of the episode, she tries to flirt with the sloth hero that punches out the Cow by asking him what he wants for dessert.
During Mighty Mouse's dream of being married to Pearl Pureheart in "Mighty's Wedlock Whimsy", it is briefly shown that they have a son, whose body shape and utterance of "Moo" heavily implies that the Cow is his biological father.
"The Bat with a Golden Tongue" has Bat-Bat's addiction to telling jokes being used as an obvious parallel to drug addiction. The scene of him begging people on the street to hear his jokes is even a not-so-subtle reference to how addicts can become desperate for money to continue indulging in their habit.
"Mundane Voyage" begins with Pearl Pureheart in peril when a man called Cardigan has her strapped to a slab as a scummy-looking man attached to a pendulum lowers down to her with his arms reaching out, implying that he intends to grope or even rape her. It's especially telling that Mighty Mouse remarks about Cardigan and the lecherous-looking man needing time alone after he rescues Pearl and puts Cardigan in her place on the slab.
In the second issue, one of the stagehands has a "Playmouse" magazine in his pants pocket.
A rather racy exchange is given between Pearl Pureheart and Mighty Mouse's alter ego Mike Mouse in the sixth issue.
Pearl: You're scramming to satiate your obsession with ice cream?! You'd better bring me back a double dip!
One story in the seventh issue has Mighty Mouse answer questions about the Mices on Infinite Earths storyline. He answers a question about seeing more of The Mighty Heroes by saying that the Comics Code Authority would shut them down if we saw any more of Diaper Man, humorously suggesting that Mighty Mouse misinterpreted the question as asking if the Mighty Heroes would be in a state of undress.