She wants a souvenir

"Oh My Goodness!" Abby gasps happily, shuddering as she grinds her rump to milk the last drops of seed out of you. "That was great! Thank you Dean! That hit the spot!"

You chuckle at her infectious happiness, your enjoyment of the eager teen's body overriding your guilt at plundering another cookie jar. Abby was so wanton and enthusiastic it was impossible to feel you were taking advantage of her. More likely the other way round, you smile to yourself as she slips off your cock and picks up her panties to mop her dripping cunt.

"You must have dumped a pint in me!" she giggles, looking at you over her glasses with teasing eyes. "If I wasn't on birth control you'd surely have put a baby in my belly, filling me up with all this come! You sure can fuck! My poor kitty is all stretched out from your fat cock!" She bends and rummages in her backpack, tucking her semen stained panties away and pulling out a permanent ink marker. She takes the cap off and hands it to you before hopping up on the desk and spreading her thighs, pulling her skirt up to show off her pussy to you.

"Sign me!" she giggles as you frown in puzzlement. "Me and some of my friends are having a contest to see who can fuck all the men teachers first. Sign my mound, or my inner thigh, or something so I can prove I did it. If you don't want to sign your name just make any mark. As long as you use the same one for every girl, it doesn't matter."

"You're having a contest?"

"Yeah! It's so cool. There's five of us. We came up with it last night. First girl to bang all four men wins. You're my first! I hope all the other men are hung as heavy as you! Or maybe not! If they are I'll be walking bowlegged!"

"I'm not going to sign my name on a student's pussy," you say, shaking your head.

"I get it! Just make some doodle. As long as it's the same for everyone, it's cool," she urges. "Please Dean, I'm not trying to get you in trouble. I just want to win. And I'd like to sample your cock again soon! Contest or not! You're a terrific fuck!"

You can't stop yourself from chuckling at her bubbly eagerness. You think a moment and then mark three inverted chevrons on her mound, just above her slit.

"There you go Abby," you laugh. "Dean Hawkfeather was here!"

"That's so cool!" she squeaks, looking down at the mark with a grin before hopping off your desk and hugging you. "This is so fun! You'll love it when the other girls get to you! But I was first! Thanks so much!" She gives you an excited kiss, her tongue halfway down your throat for a moment, before straightening up, grabbing her backpack and swaying out of the room. At the door she turns and blows you a kiss with a little finger wave before letting the door shut behind her. A moment later it pops open again for her to stick her head back in.

"Oh and don't worry about talking to Ms. Naylor. I already did that! It was just an excuse to talk to you! Bye!"

You chuckle as she leaves and you put your cock away and stand up. You wonder if your old CO had envisioned anything like this when he was briefing you for the job.