Harry Potter and the Connubialis Hex/Hogwarts Express/Lavender, Parvati and Padma/Keep his eyes shut
From Create Your Own Story
As he kept his eyes closed, the hand was going higher on his thigh. Harry's annoyment was slowly turning into arousal. His dick was now responding. Embarrassed giggles were heard. Most probably, the girls saw his erection building up, he thought.
That's when he felt a finger gently stroke the front of his pants, making the bulge more obvious to the eyes. He recognized the voice of one of the Patil sisters whisper "No!".
What will Harry do?