Rape is an intimate form of assault on a person that is considered a violation of proper interpersonal contact between people of any age or gender. In real-life the most common form of rape is sexual, while in fiction this can also extend itself to mental assaults through telepathy, magic, or other supernatural means. This does not appear at all in mainstream Smurfs media due to the stories mostly been written for children.
Since this is a very sensitive topic, please do not use graphic language in your depictions of rape in your fanfiction stories.
Empath: The Luckiest Smurf stories
Empath in the EMPATH: The Luckiest Smurf story series as well as his friend Polaris Psyche avoid using their telepathic abilities for invasive procedures that can be considered rape, with Empath being a past victim of such mental invasion by the Psyche Master when all his memories as an infant were erased. However, the Mirror Universe version of Empath has no problem using his telepathic abilties in such an invasive manner, enjoying how much it hurts his victims.
In "Papa's Big Crush," Empath prevented Smurfette from being physically violated by Papa Smurf when he was under the effects of the "pheromone cologne" by having Tailor sew up a Smurf-sized doll resembling her and by having Brainy create an artificial version of Smurfette's scent so that Papa Smurf would be attracted to the doll carrying the scent instead of Smurfette in order to satisfy himself.
In "Smurfed Behind: Smurfing In Heaven", Heftargan taunted Empath by claiming that he had sexually assaulted Smurfette while his fellow Schliphargons killed all the Smurfs, provoking Empath into nearly killing Heftargan until Polaris Psyche got Empath to stand down, sensing that Heftargan is using disinformation to undermine Empath's efforts in rescuing his fellow Smurfs from their never-ending time-travel trip during The Lost Year.
In one of the stories from "The Smurf Impersonators," when Duncan McSmurf at the Mr. Smurf Contest is asked by Sassette what he would do if someone were to try taking advantage of Smurfette at the Harvest Moon Ball, his answer was that he would "take the poor miserable excuse of a Smurf outside and smurf him such a lesson that he will think twice of ever smurfing himself upon such a fair noble maiden like our dear lassie" -- a response that made Hefty assume that Duncan was talking about him doing that.
In the Smurfed Behind saga story "The Other Side Of The Mirror," the Smurfette of the Mirror Universe is constantly mentally assaulted by that universe's Empath, who enjoys invading her mind for his own sadistic pleasure.
Hero: The Guardian Smurf stories
In the HERO: The Guardian Smurf story adaptation "The Grey Smurfs", the closest depiction of rape is when the Grey Smurf versions of Smurfette and Wonder tried to force themselves on the normal versions of Smurfette and Wonder when they were held as captives of the Grey Smurfs and forced to marry the Grey Smurf Hero in exchange for their fellow Smurfs' freedom.
In "Smurfette's Crazy Love", Hero prevented himself from being violated by Smurfette when she was transformed by the effects of being in physical contact with him during the time she had the "Hero dream" by having Tailor sew up a Smurf-sized doll that resembled him and then used his Ki energies to transmit his scent onto the doll so that Smurfette would be attracted to the doll carrying the scent instead of Hero in order to satisfy herself.
Aeon of the Champion (AoC Universe)
Depictions of this act will be somewhat more intense than in other fanfiction works, so trigger warnings will be placed appropriately wherever needed (so I don't get sued already).
One early example of rape, or at least, 'attempted' rape, was during the Sin War when the Succubi Princess Lilitu tried to corrupt Anariel using her dark spells to twist her sexuality and deform her into a lesbian. Because the archangel was clad in holy armour Lilitu's spellcasting had no effect on Anariel, who was able to defeat and incapacitate the succubus by imprisoning her in a light halo.