Jade herself later performs one of these on the Master of Games when she and Raven are fighting him at the end of the Tournament of Villainesses.
In Shinji and Warhammer 40k, Shinji mentally complains he can't kick Gendo in the teeth because he's too tall, resulting in his mental Farseer giving him some sage advice:
Farseer: How is that a problem? Remember, plan sequentially. Kick him in the shin, first, and when he lifts his leg to rub it, you may punch him in the genitals. THEN when he's kneeling is WHEN you may kick him in the teeth.
In Origin Story, Alex Harris manages to land several brutal kicks on Ragnarok's crotch, and finishes him off with a swing to the jaw with his own hammer.
In The Bridge, Sonata Dusk manages to defeat a human form Monster X by hitting him in the groin with a fence post. Since he had never been human before, he didn't think to guard it. He staggers around complaining about humans having such a pathetic weak spot.
“Look, if Tzeentch were to actually appear before me after all this in a form with balls to knee instead of some sort of gibbering, tentacled monstrosity capable of driving lesser beings mad with the merest glimpse, then I think it is fair to say that He is asking for the patella to connect with the groin. It will probably even be part of one of His plans, so I honestly won’t feel bad at all,” I explain with bitter annoyance at being underestimated, again.
[James Potter] accidentally kicked Lucius in the balls eight times as he stood up with the man's wand.
In Empire when Snape is teaching Harry etiquette of the wizarding world it's related that the appropriate way of meeting and greeting harpies is to leap around on one leg so that they'll laugh and forget to castrate the male wizard greeting them.
Ladies, and Gentlemen, an INVERSION! The groinsaw from Thirty Hs.
In the Mind Games arc, Diamond Tiara gets grabbed by a stallion who is heavily implied to be a pedophile. She screams to get everypony's attention, letting them know what the guy is trying, then bucks him in the groin. She runs away and leaves him to be beaten up by the crowd.
Shining Armor receives a pretty brutal one from General-Admiral Makarov (the Big Bad of his arc) during their fight. It involved Makarov's antlers and had enough force to throw him into the air. Fortunately, Shining had armor protecting him, but still took a hard enough hit to disable him for a time and leave bruising. While played for drama at the time (since Makarov IS trying to kill him), the bruising is played for laughs later on, when Minuette is helping a doctor patch him up and seems a little TOO interested in checking the damage.
In a flashback, Shining Armor went on a date with Rising Star. When he gets bored by her story about her ex boyfriend, she throws him across the room, bucks him in the groin, and storms off.
Fluttercruel: Okay, so good news bad news. Bad news, apparently they know about the Stare. Good news is, they're still vulnerable to getting nailed in the stallionhood...and it's still hilarious. (Notices she's being stared at) What? It's important information.
The Cutie Mark Crusaders manage to take out a Changeling by Applebloom bucking his 'apples' then Silver Spoon dropping a very heavy book on his head as he's curled up in agony. Rainbow Dash actually suggestions this tactic later.
Silver Spoon: Yeah yeah, it's low, but we're FOALS! We only have two places we can kick to actually hurt an adult! And kneecaps weren't gonna do it!
In Six Brides for Two Sisters, Shining Armor mentions how Cadance has the strength of an earth pony and "shouldn't kick a pony there unless you're absolutely sure," heavily implying this.
Shining Armor can't catch a break and in Stallions Of Harmony Verse gets one from Rainbow Dash, after tackling her into bushes in an attempt to hide her from Blueblood. The way it looked, she was fully justified in treating him like a molester.
In Kitsune no Ken: Fist of the Fox, Suigetsu makes an attempt to hit Naruto in the head with a baseball during their physical education period at school. Naruto's response? He hits Suigetsu's very next pitch back at Suigetsu and straight into his nuts. Cue Share the Male Pain from every guy in the vicinity.
The Child of Love: In chapter 7's omake Asuka kicks the writer’s groin hard after an “It must be that time of the month” comment.
HERZ: Shinji was practicing with his gun as trying to dodge Kurumi's advances. Then Asuka showed up with a sub-machine gun, selected a target at 100 meters, blew off its crotch and head with perfect accuracy, grabbed Shinji and dragged him away.
The One I Love Is: In chapter 7 Asuka was sleeping on her bed when someone fell on top of her. She woke up, and thinking a pervert was attacking her, kneed his groin. Then someone switched the light on and she saw the intruder was Shinji. Oops.
I don't know how she managed, but Asuka ended up on top of me and jammed her fist in my face, followed by her knee in my crotch.
Ritsuko: "I wonder if they even have reproductive organs there?" Misato: "If they do, I'm actually feeling a little sorry for the Angel."
Parodied in "Father Knows Best" -by the author of Nobody Dies and Walking in the Shadow of Dreams-. When Misato hears Shinji screaming, she believes that Asuka has kicked his groin. When she questioned Asuka, though, the redhead replied she never did anything of the sort, and Misato's assumption was dumb.
“So, let me get this straight. You kicked the bed and he screamed because you woke him up and he fell off the bed.” Misato cocks an eyebrow and stares across the kitchen table from Asuka, who has a look of complete innocence on her face. The redhead scoffs, arching her chin. “This isn't a manga. Or at least, that kind of manga.” Misato sips her beer, eyes level on the pilot. In the background, she can hear the shower running. She has a point. If Asuka did kick, with full force, into the most sensitive of sensitives Shinji wouldn't be able to walk, much less run to the bathroom to get ready for school. She's seen the girl kick and there's a good chance she could have kicked it clean off.
In Evangelion 303 Asuka warns Shinji that, if he ever cheats on her, his punishment will involve electricity and testicles.
In Sailor Moon Princess, after a wild party, the girls search through Mamoru's laptop only to find erotic picture of them on there, so when he enters the room, both Rei and Makoto kick Mamoru's groin in anger. However, they later find out that it was really Haruka's laptop.....
Guide Me Home; during a sparring match, Hakoda pins Ursa against a wall and accidentally touches her burn scar. Ursa panics, Groin Attack ensues and Ursa is completely mortified afterwards. Yes, that is an actual tear jerker example of this trope.
The Seed of Batman, where Batman suffers multiple doses of Groin Attack, blowjob, handjob, etc. For huge doses of humiliation, those who give him this are prostitutes, whose boyfriends (or pimps) have been imprisoned by Batman so they want to take Revenge by humiliating him. In Chapter 3, Candace and a henchwoman take it further by raping him while framing him as if it was Batman who raped them.
In Ah,Nuts!, John and Roy tangle with a druggie who turns violent and directs his anger at John, biting him in the groin. He yelled that he hoped he bit it off, but John escaped with a wound on his thigh and scrotum that Dr. Brackett had to suture at Rampart. He is embarrassed, but Roy reassures him that he really had nothing to be ashamed of, and that the guy was awful for wanting to permanently disfigure him.
In Cub Ron tries to pull ex-girlfriend Hermione into an alcove and when he turns around to talk to Draco Malfoy she kicks Ron in the balls.
In the opening scene of Mirrored, Voldemort demands that Harry kneel before him or he will kill Ron and Hermione. Harry complies but takes this opportunity to punch him in the balls. Ron decides that was the most awesome thing ever (and won't shut up about it) while Hermione cautions that this will no doubt have repercussions seeing as Voldemort was only out to kill him before.
Harry: Hello, Krum. While I know that I'm probably going out of bounds with this, but I just wanted to let you know that Hermione is my best mate—she's like a sister to me. So if you hurt her in any way, I'll not only hex your balls off, but I'll also make the rest of your life a living hell. Just so you know—for future reference.
In Souls Abound Millicent Bulstrode kicks her father in the crotch when he tries persuading her to let Voldemort's spirit possess her body.
In Unconventional Harry Ginny hits Draco Malfoy in the crotch with the bag containing Harry's Triwizard Tournament winnings.
This is lampshaded by Deimos's statement: "The final tenet is fight dirty. This isn't a duel nor is it a time to be fair. Gouge your opponent's eyes, gang up on one opponent, use groin attacks, whatever it takes it defeat your opponent."
One chapter has an enemy dinosaur bound to a tree and beaten severely, including several kicks to the groin.
Another chapter has Ducky's mother, armed with twin sticks disable another dinosaur by striking his weapon arm with one stick, tripping him, then kicking him in crotch.
The most brutal groin attack in this story involved a dinosaur kneeing his enemy in the groin, ripping out one of his opponent's eyes, tripping his opponent and almost literally ripping his opponent's head off.
They're reptiles. How does that even work?
Research be damned! It's too much of a good story to let facts get in the way.
In The Legend of Spyro: A New Dawn, Cyros kicks her younger brother Pyros in the groin, then stomps on him there when he says she'll lose a bet, one of her Berserk Buttons. She does it again in the final battle between them to gain the upper hand in their fight.
In The Life And Times Of A Winning Pony, this is taken more seriously than most examples when Cloud Kicker delivered a nasty blow to Rainbow Dash's groin, resulting in her nearly bleeding to death. The incident was probably also a major factor in Rainbow Dash's asexuality.
In The Chase is one of the examples where this happens to a female. Berry breaks the 'peace' between House Avarice and Clan Pickled when she justly delivers a beating upon Primrose Propers. She also ensures no more foals will be born to such an undeserving mare.
In the Empath: The Luckiest Smurf novel, Smurfette gives one to Hefty for his saying that Empath couldn't possibly feel a thing for her, with her retort being that Empath would feel more for her in his heart than he would in his private area (insinuating that is how Hefty feels for Smurfette).
In Chapter 12 of An Unexpected Child, Bruce actually punches Alice in the dick, causing her to fall over and knock down a pillar, which then falls on part of the circus audience and crushes them to death.