My friend is a magic girl is pretty funny. https://exhentai.org/g/1113640/ecf0ce14bb/
Synopsis: A few years ago evil aliens led by the demon lord invaded and then magical girls appeared to fight them with power given by aliens. A certain middle school girl has a lifelong dream of becoming a magic girl and her brother and her guy friend both tease her for it, the later saying, "If you were to be a magical girl no one would want to look at you!"
and when a monster attacks the city she knows a magical girl will show up to fight it, and she asks her guy friend to come with her so she can finally see a magical girl in person and so they can take photos.
Her friend tries to talk her out of it saying we should go because it's dangerous, but she insists that it's her dream to meet a magical girl no matter what. And I want to meet the person I love! He is moved and says, "Rika, hold my shoes for a moment." Then to her bewilderment he screams, "Miracle Shine Star Change!"
He transforms into a magical girl who still talks like a punk. He tells her to stay back becaude she's about to see a real magical hirl battle. She says she wants to return what he said to her earlier (meaning she doesn't want to look at him as a magical girl.). And he covers his panties and tells her, "Then don't look!"
Then he beats the monster with a punch and then talks to his stunned friend.
He explains how it happened: one day he was walking home when aliens abducted him and offered him a wish, Kyubei style, as long as he fought for them. He says He just longs to go home, but the alien says the dream needs to have more power.
He says with a blush, "Hypothetically, maybe to attract the attention of the girl I love?"
The aliens says, "Good enough/You're eligible" and then he turns into a magical girl. (Of course he keeps this part a secret from Riku, which implies she is the one he loves.)
He tells her not to tell his secret anyone because it would be embarrassing, but she threatens to tell her class if he doesn't do where bidding, and he has no choice but to agree. She then asks why he hasn't seen him fight before and he says he didn't make his official first appearance because sometimes his transformation fails (and then he's a boy in a dress.)
She says it's a good thing yoi're not middle aged, because then the failure would look even worse. Just then a middle aged guy appears and tries to do a transformation but fails. The MC greets his middle aged friend, and tells her he told his friend. Middle aged guy tells her it's common for boys to be magical girls....all the magical girls he knows are really guys. She says she feels like her dream has been broken. He says many that's why we keep it a secret, to protect many people's dreams...(except yours.) Guy friend apologizes for informing her about reality.
Then Riky asks which magical girl the middle age man is and he says Myuu, and she gasps recognizing he's the really cute magical girl who always shows up late--usually too late to fight the monsters (and now she knows the reason is he doesn't want to be caught in a failed transformation.)
Then the monster from earlier wakes up and Myu beats it in an amazingly cute way. Then the evil demon lord says a new magical girl had appeared, and dispatches someone to "meet" him.