A buff dude went to the local park that has a wishing fountain. Muscle bro wants to be a cool badass protector with magical abilities. Unfortunately, "Fountain Bro" decided to grant him his wish in a different sense.
"Fountain Bro": "Congratulations! You are now a 14 year old middleschooler who can transform into a magical girl with magical powers while you also fall for a college student. No refunds on any coins tossed in! Enjoy your new life. Oh also this has side effects. Any friends you have will also become magical girls and your minds will mentally shift into your new forms. Alright bye!"
Muscle Bro is now Usagi Tsukino (or Serena) where he...or she will:
Fight evil by moonlight. Win love by daylight. Never run from a real fight And so on.
Seeing big buff muscular males getting turned into these super cute and short beings or into a girl is a favorite trope of mine and I plan to draw more of these situations.