Invoked during the twentieth chapter (adapted in the sixth episode). Moe brings her desserts in and fans at the Astronomy Group to induce this, as they Forgets to Eat.
During the thirty-fifth chapter, while on the taxi out of the Ishigaki airport, Ao has this because she's on a shoestring budget and has to forego lunch.
Ben-To has people fighting over discount food, and the hungrier they are the more motivated they will be to fight. So it uses this sound as a cue that the everyone is ready for a fight.
Happens to Orihime a few times after she denied being hungry when Kukaku Shiba served Ichigo's group dinner in "Assemble The 13 Divisions", leading to her aggressively punching her stomach to shut it up, much to her friends' horror.
This also happens to Rukia during a flashback to her days as a Rookie Soul Reaper in the episode "Testament, Your Heart is Right Here", used as an example of how training too hard would cause her to lose sight of more important things, such as keeping herself fed.
This happens to Nelliel in a flashback sequence during episode 194, where she gets so hungry while looking for her Arrancar helpers that her stomach starts growling. Before she can go eat though, she runs into the unpleasant Nnoitra who has attacked the ones she's looking for, and things get ugly from there.
During episode 39 of Blue Dragon, Shu and friends are bored out of their skulls as they're forced to attend a ridiculously long speech, but a bit of levity is provided by Bouquet and Kluke's growling stomachs. Shu cracks up, Bouquet is amused, but Kluke is just upset.
Brave Police J-Decker: In episode 11, a hungry Shadowmaru's fuel tank growls in front of Azuki, prompting him to get flustered.
Brave10: Happens when Saizo meets Isanami and she offers to buy him food, despite his reluctance to get involved.
Yolei: [after her stomach growls] We don't need a translator to explain that. Sora: We may not understand each other, but growling tummies are universal.
From Digimon Fusion, Archelomon's stomach growled in the episode "Island Zone in Chaos", making the group stop for lunch. Wisemon's stomach growled in the episode 'Lost in Digital Space', due to forgetting to eat because he was studying.
Thanks to being one of the archetypal Shonen heroes, massive appetite and all, this happens to Goku a lot throughout the franchise. Noteworthy moments include the time he actually tries to forgo eating to keep Krillin from having to find his belongings for him in the original Dragon Ball, and him scaring King Kai with the ferocity of his stomach's rumbles while training in Otherworld in Dragon Ball Z.
In episode 47 of Dragon Ball Super, Future Mai denies being hungry when Future Trunks offers her food. Unsurprisingly, thanks to how hard food is to come by in the bombed-out hellscape created by Goku Black, Mai's rumbling stomach gives her hunger away and prompts her to accept it.
In episode 4 of Dragon Ball GT, Goku complains about being hungry due not eating for so long. Pan makes a snappy snide remark about Goku always being hungry, only for her growling stomach to make a hypocrite out of her. Unsurprisingly, she's suddenly a lot more open to finding food.
In the 4th Dragon Ball movie Path to Power, Bulma gets so hungry after being imprisoned that her stomach starts growling. Thanks to a poorly-worded remark on her end, Oolong freaks out, afraid that she's seriously going to eat him.
Fullmetal Alchemist: This happens to Edward due to hunger in the episodes "Be Thou for The People", "The Phantom Thief", "Bonding Memories", and "Father".
Fushigi Yuugi: In episode 45, Miaka and Tamahome are about to have sex before the Final Battle (in spite of Miaka's Virgin Power, just in case Tamahome dies). Just before they go all the way, Miaka's stomach grumbles, which creates a lot of awkwardness. (Miaka is embarrassed, and Tamahome loses his mojo.)
Future Card Buddyfight: In episode 4, Drum's stomach growls while he's wandering around the city, making him stop at a takoyaki stand. Batzz's stomach growls in episode 38 of Future Card Buddyfight X, having worked up an appetite from a day's worth of training.
On Glitter Force, it happened to April, Kelsey, and Chloe in "The Lost Girls", due to being starving while looking for Emily and Lily, and to Candy in "Kelsey Gets a Makeover", leading Emily to use the Glitter Pact to conjure up a strawberry for her to eat.
GUN×SWORD: In the pilot, Van's growling stomach is the only warning that he's about to collapse from hunger.
In the episode "Stan and Sandy Make Up", while the Ham-Hams are making a big birthday cake for Stan and Sandy, Boss' stomach growls in the process. After they finish, Hamtaro and Bijou admire the cake, and both their stomachs growl at the exact same time.
In another episode this happens to Nin-Ham. He was hungry after his long journey.
Kirby: Right Back at Ya!: In the episode "Island of the Lost Warrior", Kirby gets stranded on a desert island with Tiff, Tuff, Fololo, and Falala. While Tiff tries to think of a way to get off the island, her stomach growls, and they forage for food.
In "Delivery Dilemma", King Dedede's stomach growls multiple times while he's waiting for his food delivery to arrive.
Mitsudomoe Zouryouchuu!: Episode 2 has Mitsuba skip dinner after Miku makes fun of her pudgy waistline, and her stomach growls right when she's out of earshot of the rest of her family. As a Big Eater, she finds her desire to lose weight quickly at odds with her appetite.
Monster Musume: Near the end of the episode OVA (13), all the monster girls' (and Kuroko's) stomachs growl at the same time, resulting in one hella loud growl that echoes through the streets. Fortunately for them all, Kimihito's feeling generous and treats them all to dinner to their delight.
My Monster Secret: Occurs as a Running Gag, where Youko's attempts to be a "cool beauty" are often undermined by her stomach growling. It's even been used to find her in at least one chapter where she was trying to hide from someone.
One Stormy Night: Played for Drama when Gabu the wolf desperately fights his hunger because his best friend Mei the goat offers himself as a meal to Gabu.
Panty & Stocking with Garterbelt: In episode 11, the titular angels are bored out of their minds and starving, as shown by the monstrous growls their stomachs make. With nothing better to do, they order a ton of food and pig out, gorging themselves to the point that they turn into massively bloated spheres that serve as the page image for Balloon Belly.
Pecola: In "Yeti or Not", Coco and Rudy both mistake Pecola's stomach growling for a roaring yeti.
The Pet Girl of Sakurasou: Happens to Nanami while talking to Sorata at school in episode 5. Sorata offers her a snack he was holding for Mashiro, but she declines it initially, claiming to be on a diet. However, her stomach growls again, and she reluctantly takes it. The more likely reason this happened was because Nanami didn't have enough money to buy food due to saving up for school on her own.
Pokémon: The Series: It would make a pretty good drinking game as to counting how many times it would happen to Ash Ketchum. As another iconic Big Eater Shonen hero, his stomach rumbles countless times due to genuine hunger as well as him simply being a glutton. Standout moments include his growling stomach annoying May due to potentially scaring off an Arcanine they're tracking in "On Cloud Arcanine", and him scolding Shauna for wanting to postpone a match until she's eaten only for his stomach to speak up in "A Meditite Fight", among others.
May's as much of a glutton as Ash, and has had this happen to her a few times as well. In "You Never Can Tailow", her stomach growls thanks to a particularly feisty Tailow stealing the only food she and the gang had, and a similar occurrence happens in "Go Go Ludicolo" when the group has to give up their lunch to a trainer Ash lost to as part of a bet, much to her displeasure. And in "Hail to the Chef", May's growling belly is what prompts the group to check out a restaurant they found in the middle of a forest, but not before Brock and Ash tease her for it.
Team Rocket is also prone to this, due to constantly being on the road and out of food due to the constant misfortunes that they face. One such example happens in "A Lean, Mean, Team Rocket Machine" where their growling stomachs lead to them pigging out at a buffet and packing on the pounds, only to for hilarity to ensue as they desperately try to work off the excess weight. Another memorable example is "Ignorance as Blissey", where a helpful Blissey helps quiet their growling stomachs by feeding them, leading to Jessie realizing that she was friends this specific Blissey when she was training to be a nurse leading into one of the saddest episodes in the series when they have to go their separate ways at the end.
In "Here comes the Squirtle Squad", Jessie's stomach lets out a monstrous growl right after she slaps James and Meowth for wanting to break for lunch. Flustered, she decides that they have a point, only for the Squirtle Squad to steal their picnic lunch right when they're about to eat.
While she and her Lucario try to meditate in "Crossing The Battle Line", Maylene's stomach starts growling much to her Pokemon partner's annoyance. Since he doubts that she's taking her status as a gym leader and a martial artist seriously, she takes time to reassure him that's as committed to her job as ever.
Happens to Shauna in "A Meditite Fight", where her stomach's grumbling interrupts a battle between her and Ash before it even begins. Since he was eager to fight, Ash isn't amused when she tries to postpone their battle for lunch.
Korrina's stomach growls, as does her Lucario's, right after defeating Ash in "Mega Revelations". Deciding to break for lunch, Korrina takes some time to talk to the gang about the history of Mega Evolution, as well as her desire to achieve Mega Evolution with her Lucario friend.
In episode 7 of Suite Pretty Cure ♪, Kanade's stomach rumbles when she passes by a diner while searching for Otokichi.
In episode 2 of Smile PreCure!, Candy's stomach rumbles, prompting her to show Miyuki how to use the Cure Decors. With the Decors, Miyuki summons a giant strawberry, which Candy eats all in one go.
On HappinessCharge Pretty Cure!, it happens to Hime on episode 6, while waiting for Ribbon to finish making lunch, and 21, when the other girls try to tempt her out of her room with cream stew.
In episodes 24 and 26, Ciel's stomach growls due to hunger causing her to transform back into her fairy form, Kirarin, whenever she gets too hungry.
During Yui's cameo in the final episode of Tropical-Rouge! Pretty Cure, she's very hungry, and has a loud stomach to go along with it.
In the first episode of Delicious Party♡Pretty Cure, Rosemary hadn't eaten before leaving for Oishiina Town, and as such has a very noisy gut when he arrives (and then passes out on a bench from overwhelming hunger).
Tamagotchi: Kuchipatchi usually winds up being the one whose stomach growls, since he's Obsessed with Food and thus very hungry a lot of the time.
Wagnaria!!: Happens a lot like Kyōko in the episode "Wagnaria's Big Stomach" and episode 3. Yamada's stomach growled in episode 12. Episodes 9 and 11.
In Yu-Gi-Oh! ARC-V, Yuya's stomach growled in the episodes "Genius Master Chef Michio Mokota" and "An Exciting Performance! A Fulfilling Meal!" due to not being able to have breakfast before leaving for the duel and thus being hungry throughout it.
In the Yu-Gi-Oh! SEVENS episode "No More Holding Back", Romin's stomach growls from hunger during her duel with Gakuto, and she's unable to control it. Things get crazy from here when she becomes an intense rocker and duelist as she is "hangry". Luckily, at the end of the duel, she presses the button on her Duel Guitar, and a chocolate bar pops out of it for her to eat it.
Gas and/or gut trouble
Cowboy Bebop: In "Mushroom Samba", Faye's stomach grumbles due to stomach pains caused by eating rations that were a year old.
In Episode 3 of Hirogaru Sky! Pretty Cure, Kabaton's stomach moans after he eats mushrooms that he didn't know were toxic.
An unconventional example appears in chapter 77 of Seitokai Yakuindomo. In the middle of a Student Council meeting about cafeteria menus, Aria gave out one that others initially thought was due to the topic of discussion. It turned out it was due to Potty Emergency—she administered herself an enema for the sake of masturbation.
