A Steph
A Steph is someone who thinks fart jokes are the worst thing since sliced bread and would rather be hit by a bus than laugh at them.
My friend is a Steph. I told her a fart joke. She stared at me like I was a monster.
At the party, Steph didn't laugh when Mark farts. He cried.
My Steph cousin called me a loser for not laughing at her brother's fart.