(1) Professor Evans X Headmaster Riddle

The first time Tom Riddle met Lily Evans, she was eighteen, nearing the end of her third year at Hogwarts and despite being a Gryffindor, was roaming the balls of Hogwarts in green lingerie in search of cock.

He'd been refused the position of Professor of Defence Against The Dark Arts, so the chance to release that anger into the cunt of an eager slut was ideal.

The next time he saw her, was five years later. Wormtail, a spy, was reminiscing about sluts and it turned out quite a few **** Eaters had sampled Lily Evans. Hearing about the nasty married slut inspired Riddle to call for a very special raid and Wormtail was happy to sneak them all to where the Potters were staying.

Pregnancy had made Lily's even more sinfully sexy and her marriage to James Potter had frustrated her to the point she was even more sexmad. Riddle never thought gangbanging a slut would be the secret to killing Dumbledore, but it was effective and fun.

Fast forward a dozen years and with Flitwick retiring to spend his days knocking up Goblin Girls and Witches locked in the Gringotts Debtor's Prison, he needed a Charms Professor. And he received a letter from Lily.

She was a week late. To mark her daughter turning eighteen, Lily had gone for a holiday in France and gone without contraceptives. Two pregnancies later and she'd regained her tiny waist and received bigger, milkier, KK-Cup udders. Naked in his office, those massive years were leaking milk all through her summary of her lesson plans for the school year.

He sank his cock into her arse. If she wanted him to put another baby into her, she needed to impress him. And he was sure whatever it was would involve sex and probably also their daughter Ruby.

What Next?
Option 1- Harry Potter is on the Train, looking for his sister
Option 2- Durmstrang's Celebrity Viktor Krum has an interlude with his Dark Arts Teacher, Bellatrix Black
Option 3- the Welcome Feast
Option X- Open to Suggestions