Basic Trope: Gay characters die in the course of a story.
Straight: Ted and George are gay, and Alice and Bob are straight. All four fight the Big Bad, but George dies. Ted is left alone miserable while Alice and Bob live on.
Ted, George, Alice, and Bob all fight the Big Bad. During the dramatic climax scene, Alice and Bob manage to escape. However, Ted and George are left behind, and die so horribly that no one is gay ever again.
The Big Bad's plot involves murdering all gays... and it works.
Downplayed: There is an equally balanced cast of gay and straight people, and an equal amount of them are Killed Off for Real.
The Big Bad is a crazy homophobe who actively focuses his efforts into killing George and Ted while practically ignoring Alice and Bob.
Being gay in real life, has been and still is often prone to its downsides due to the prejudice from other social groups. In some countries you can't even get married if you're gay or have children in a same sex relationship, and you might have trouble being accepted by your peers, family or your religious group. The author uses this trope as he/she is gay and is using this trope as a metaphor for how society makes life harder for being due to their orientation and reflects the hardships he/she has been through.
This show is set in a Crapsack World; EVERYONE is either miserable or dead at the end. There is simply no exceptions made for characters on the LGBT spectrum.
Inverted: Bob dies, Alice is miserable, but Ted and George go on with life.
Subverted: It seems like George has been killed, but he manages to survive with an inch of his life thanks to sheer determination.
...Sadly, George only lives long enough to die from his injuries later in a hospital.
Alternatively, as George goes to inform his same-sex love interest he's okay it turns out the love interest died of something totally unrelated to the rest of the story.
Parodied: Alice, Bob, Ted, George, and Stella all go fight the big bad. Ted and George die immediately, and Alice, who is pretending to be Stella's girlfriend so she can repel another girlfriend, is killed too. This makes Bob, Alice's real boyfriend, complain. Somehow Alice is magically revived.
Discussed: "Bob's crush on Joe doesn't speak well about his chances."
Conversed: "Have you ever noticed how gay characters seem to have a higher mortality ratio than any straight co-protagonists?"
Deconstructed: George considers himself an inferior person as a gay man, due to his conflicted religious views and sexuality. This leads him to care less about his own life and take too much risk in a battle, leading to his death.
Reconstructed: This leads Ted, who also considered himself an inferior person, to to come to terms with his sexuality and persevere.