Harry Potter and the Connubialis Hex/Hogwarts Express/Neville, Luna and Romilda/Come in Luna's mouth
From Create Your Own Story
"Stop Luna or I'll come in your mouth".
She heard him but his body was telling her something else. She acted like he didn't say anything and blowed him harder. She could hear him panting as he was trying not to come.
"Luna, don't...." It was too late. She got a little surprised when she felt the hot fluid in her mouth. Romilda removed Harry's rod from Luna's mouth and sucked that was left. She brought her mouth to Luna's and mixed tongues. When they separated, Harry saw them gulp.
They giggled as they swallowed what was left of Harry's cum. They looked at him and smiled. Harry was flabergasted and couldn't do anything else than smile back.