Your hand is still working your large, bright red, swollen cock when powerful muscles in your crotch tense up. It's starting - reality sinks in that you're about to have your first canine orgasm.
And then the door opens. You see your roommates face appears in the doorway and goes into a blank expression. And he's not alone - several other familiar faces surround him. He's brought his friends, and they are all seeing you right now - embarrassing enough in its own right, but even worse now that your new arrangement is available for everyone to see.
Obviously, you take away your hand immediately, but it's too late! You've crossed the point of no return. Your body freezes up, your crotch feels warm, and you feel the contractions as long ropes of semen start erupting from the pointed tip. You would be enjoying this thoroughly if every wave of pleasure weren't a pang of humiliation.
You spurt for what seems like forever, never having imagined that a dog could cum that much. Everyone's eyes are wide while the last dribbles of sperm drip out. You're still prominently erect, your knot swelled to the size of a small fruit.
You hurriedly try to pull up your underwear. One guy faints. You're babbling trying to come up with an explanation.