New Mutants: Larry in New Mutants issue #45, introduced as a bullied mutant with the ability to create sculptures from light. Classmates taunt him and leave him a note saying a mutant-hunting organization is coming for him. He commits suicide, not knowing the note was a cruel bluff.
In JLA: Superpower, the League gains a new member named Antaeus, who is a massive fan of Superman and has had his entire body cybernetically enhanced in the hopes of becoming the perfect hero. Unfortunately, Antaeus disagrees with the notion that the League should stay out of politics, and when they nix his plans to overthrow a Saddam Hussein expy, he decides to go it alone, with disastrous results. Needless to say, he doesn't survive the one-shot.
LOST: The original plan for Jack Shephard in the original outline for the show to establish Anyone Can Die. Producers feared that letting the audience become attached to a character, only to kill him at the end of the first episode, would cause fans to resent the show, so the character became a regular.
More straight examples would be E-102 Gamma, as well as the other E-series robots from E-100 Alpha to E-105 Zeta from Sonic Adventure. All these characters were built by Dr. Robotnik and destroyed by each other (or in the case of Alpha, Amy Rose) within the same game. While E-101 Beta, E-103 Delta, E-104 Epsilon, and E-105 Zeta play this straight by having not been seen in new games since, E-102's only appearance since was as an unlockable character in the non-canon party game, Sonic Shuffle and he has had expies in the forms of Chaos Gamma from Sonic Battle and E-123 Omega from Sonic Heroes onwards. E-100 Alpha's only appearance since was as an enemy in the special stages of Sonic Advance 2.
Alvin and the Chipmunks: The titular trio come across a stray kitten, naming him Cookie Chomper III. He is run over by a car, leaving the Chipmunks to deal with their grief.
As Told by Ginger: Carl befriends an elderly woman named Maude, who seems to bring out the worst of Carl's mischevious personality. She attends a dinner that Ginger arranged in an attempt to impress Courtney Gripling, only to keel over into her plate.
The Powerpuff Girls: Powerpuff Bunny, the girls' Sixth Ranger in the episode "Twisted Sister". Created with artificial sweetener, twigs and leaves and stuff, a mix of the three girls' favorite things, and Chemical X, resulting in a hunchbacked, snaggletoothed, inarticulate Powerpuff Girl. Her creation left her with an Unstable Genetic Code, leading to a Heroic RROD when she pushed herself too far saving her sisters.
Family Guy: New Brian's perfect behavior won over the Griffin family, causing a dejected Brian to move out. Stewie was not so easily charmed, and attempted to get New Brian to just leave, only for New Brian to reveal that he has been humping Rupert, Stewie's teddy bear. Cut to Stewie dragging a bloody trash bag to the curb and Peter reading an improbable suicide note.
Downplayed with James. He sacrificed himself at the end of his debut episode to save Jake, Finn and Bubblegum. The Princess makes a clone of him at the end to honor the original. His reanimated corpse appears in a later episode, while clones of him to continue to die and be replaced.
Lemonjon, a Lemon Person so large he occupies the entirety of the Earl of Lemongrab's castle. He blindly followed Lemongrab's order to attack the Candy Kingdom, prompting Jake and Finn to attack his heart. This caused him to start feeling and launch into a Purple Prose speech about suffering and the greater good. He then explodes, raining down lemon candies on the Lemon People, saving the Candy Kingdom from their assault.
Five hats means that five tropers think it is ready to publish.
You are saying that you think this draft is ready to be published. That means the description is not ambiguous,
it doesn't duplicate an existing trope, there are at least three examples, and the title makes sense.