Cucked by a futa

When you hear the key turning, you rush to the door right in the ridiculous outfit they made you wear for the whole day today; a pink t-shirt, small even for you, a comically short pink tutu skirt and the cutest pair of girl panties in the house, the pink-and-white striped ones - all from Lucy's wardrobe. You expected just one of them, but both your beloved girlfriend and the superior woman who stole her enter together. Lucy is in her regular college attire, a white blouse with a blue skirt, black nylons covering her gorgeous legs with classy black loafers on her feet. Mythra is in her usual outfit of a white tanktop which shows her deliciously toned abs, short black sports bloomers and some white sneakers. Looks like Mythra was just finishing her evening jog when she met Lucy on the way home; they don't even acknowledge a petty creature like you as they walk in, Mythra's hand is possessively groping Lucy's ass as the two rub shoulders against each other and coo about something like real lovers. When you tried touching Lucy's butt like that before, even though she was still your girlfriend at the time, she almost seemed insulted and gave you a slap; now that Mythra's doing it, Lucy doesn't seem to mind at all, almost rubbing her backside against Mythra's hand as if the touch gives her physical pleasure.