So, you're newly out of the closet. Likely in your late teens or early twenties, the world can be a confusing place for a young queer person (especially in pre-New Millennium works). How do you find a date? How do you transition? Where can you meet people similar to you?
Here is where this trope comes in.
The protagonist will meet an older character. Out, proud, and confident, they will help the lead with their troubles and be a shoulder to cry on if things go sour along the story. They also inspire the protagonist and show that not all queer people end up miserable and/or dead.
A large number of Coming Out Stories have this type of character. They're almost never a Love Interest (and oftentimes they are in a relationship already). Instead, they're more of an older sibling figure and a confidant to the main character. If they're in a relationship then they and their partner might act as a Beta Couple to the lead.
- In Bloom Into You, Sayaka, who realized her liking girls was not just a phase after meeting with Touko, seeks advice from Miyako, a lesbian café owner who's in a relationship with Sayaka's own teacher Ms. Hakozaki. It's partly thanks to her conversations with her that she eventually finds the courage to confess her feelings to Touko.
- In My Brother's Husband, Mike Flanagan, a gay Canadian visiting Japan to meet the family of his dead Japanese husband, ends up mentoring Kazuya, the gay teenage elder brother of a school friend of his niece Kana.
- Wandering Son has Yuki Yoshida, a trans woman Takatsuki meets while out as a boy for the first time. She's the Cool Big Sis for Takatsuki, Nitori, and to a degree Makoto later on.
- In The Legend of Korra: Turf Wars, the older Kya serves as this towards Korra (the titular character) and her girlfriend Asami.
- In Avengers Academy, Julie Power serves as a mentor to the newly-out Striker, though she is continually frustrated that Striker keeps using his sexuality to draw headlines.
- Implied in the Land of Oz one-shot The Road Built In Hope. Dorothy stays with a lesbian couple in San Francisco for a while. Dorothy is a bit young for romance, but her affections for Ozma are likely to develop as she ages.
- Moving is a one-shot fic for The Children's Hour film where Karen, drifting aimlessly after her best friend Martha's Gayngst-Induced Suicide, ends up rooming with a woman. The woman is a gay trans woman who helps Karen come to realization on her own bisexuality.
- Long-time gay Miss Alice Band is this to new Assassins' Guild graduate Jocasta Wiggs in Discworld fics by A.A. Pessimal. in fact, there is a possibility Alice acts as a mentor and a discreet help to young Assassin students who have reason to suspect boys will not feature more than incidentally in their lives. (She was, however, professional enough as a teacher to wait till after Jocasta had graduated. She knows where the line is and not to cross it.)
- Being unashamedly bisexual/pansexual, Minako is this to the rest of the Senshi in But You Won't Have To Do It Alone. She admits that she can't relate to her friend's gayngst well, being that she never had any issue with her sexuality, but she's always there to be a shoulder for sympathy or advice.
- In A Song Of Grumbling And Cotton Candy, Pizzazz calls her groupie Clash and her girlfriend Blaze upon accidentally asking Jem out on a date. Clash actually cheated on Blaze with Pizzazz once, but Pizzazz is in heavy denial over being lesbian and has no clue how dating women works.
- I Am J:
- After running away from home for a few days, seventeen-year-old trans boy J meets Marcia. She's a trans woman who visits the motel looking for runaway teens to give them advice. Marcia recommends that J visit a shelter for LGBT teens. She's a bit character who only appears in that one scene, but she has a major impact on J's Coming-Out Story.
- Chanelle, who goes to J's high school, is a twenty-year-old trying to graduate (with the cut-off age being twenty-one). Chanelle is a trans woman herself, and she acts as J's older sister-esque friend who helps him where his cisgender Childhood Friend Melissa cannot.
- J meets Zak, an older trans guy, at a support group for transmasculine people. He helps inspire J and is his sole male friend.
- Two of Annie's teachers reluctantly play this role in Annie on My Mind. They're closeted and in a Secret Relationship. After both they and Annie are Forced Out of the Closet, Annie begins opening up to them about her relationship with Liza. In Annie's case, she uses them as a basis on how she doesn't want her life to be. Annie doesn't want to stay closeted forever.
- Supergirl (2015): Maggie serves as this for Alex when she comes out, with this role and the related fact that they're in very different positions in life being reasons that Maggie gives for initially turning down Alex despite being attracted to her.
- In Pose, Blanca finds herself pressed into service as Damon's queer mentor because he is so virginal that he barely even knows how to kiss someone properly.
- Age-inverted in Crazy Ex-Girlfriend: Middle-aged Daryl only realizes he's bisexual when he realizes he's attracted to the much younger White Josh, who has been out since he was twelve. Despite being younger, White Josh serves as Daryl's mentor thanks to his much more profound experience with being gay.
- Mildly age-inverted on Will & Grace. Jack is younger than Will but was out before Will and even realized that Will was gay before Will did.