After five solid minutes of passionate snogging (this respiratory bypass thing could prove to be very useful, Donna reflected), she reluctantly disengaged her mouth from the Doctor's, ignoring his noise of disappointment.

"Doctor."

"Hmm?"

She grabbed his hands as they tried to slip under her top.

"Doctor. Stop it. If we're going to do this I think we should talk first. I haven't... I need to know how different this is going to be from human sex."

He sat up, pulling back from her a little.

"It's not, really. All the er, parts go together the same way."

Donna sensed that he was leaving something out.

"But?"

"But- and I'm not sure that this is even something we have to think about right now- Gallifreyan reproduction is significantly different from what you're used to."

Of course.

"In what way?" Donna asked somewhat apprehensively, hoping to god that he wasn't about to reveal that the males of her new species carried the young. Some things, in her opinion, were best left to seahorses and bad science fiction.

"Well, we're not, strictly speaking, mammalian- despite evidence to the contrary." He glanced conspicuously at her chest, "I mean, infants are fed in much the same way, but... the thing is... we're kind of... oviparous."

"English, Spaceman."

He took a breath and said very quickly, "Donnawelayeggs."

Her eyes grew round and her hand drifted unconsciously upwards in preparation for a slap.

"Sorry. Did you say eggs?"

He nodded, looking fearfully at her raised hand.

Donna sighed and lowered her hand.

"Don't look at me like that; I'm not going to hit you. It's hardly your fault."

The Doctor visibly relaxed.

"Having second thoughts then?"

"No. Yes. I don't know!" She ran a hand down her face in frustration, "I want this, I want you, but..."

She tried again, "It's not just the egg thing, although that is, admittedly, pretty weird. It's- oh, Christ, this is embarrassing- I haven't actually had sex in almost twenty years, and even then it was never good."

She wrung her hands self-consciously and avoided his eyes, "I'm not sure I'd be able to see it through, so to speak."

The Doctors mouth dropped open in shock.

"That's what you're worried about? That I'll end up frustrated?"

He reached out and gently gripped her shoulders.

"Donna, I am so sorry that you were ever treated as though you were anything less that supremely important, but please, please believe me when I say that I want nothing more than for you to be happy. We don't have to have sex if the idea frightens you or makes you uncomfortable. Whatever you decide, I... I love you."

Stunned by the magnitude of his declaration, Donna responded in the only way she could think of. She kissed him again, hard and heated, all clashing teeth and warring tongues. Almost of its own volition, her hand slid up his inner thigh to brush against the bulge of his rapidly growing erection. He made a desperate little noise in the back of his throat and pushed her off, the suction of their lips breaking with a wet pop. They were both breathing heavily, with their faces flushed and their pupils dilated.

Catching his breath, the Doctor spoke, "Donna, are you sure?"

Donna closed her eyes briefly before replying, "I... I'm sure. I want to. But... I'm still scared. I shouldn't be. I know you won't hurt me, but I still... Argh! I don't know!"

The Doctor sat thoughtfully for a minute before saying, "I have a suggestion, if you'd like to hear it."

"Alright then."

"We could- if it would make you more comfortable, we could make tonight just about you. Let me learn you, your body, your responses. Let me show you that this can be safe, that you can enjoy yourself without worrying about me."

Donna fidgeted nervously, but she couldn't deny that she found the thought of his hands on her body with no intentions other than bringing her pleasure incredibly arousing. She took a deep breath and, releasing it in a gusty sigh, made her decision.

"Okay."

The Doctor smiled, incredibly happy at this proof that she felt comfortable enough with him to allow this.

"If you want me to stop, just say so and I will, I promise."

"I believe you."

He gave her a gentle, lingering kiss before picking her up and walking across the room to lay her down on the thick, fluffy rug in front of the fire she could have sworn hadn't been lit five minutes ago. Once she was comfortably reclined, the Doctor set about divesting her of her clothing, peppering each and every inch of skin he bared with feather-light kisses. Finally, Donna lay naked on the rug, feeling pleasantly warm and tingly as the Doctor used his teeth and tongue to work her nipples into aching, hardened peaks.

Eventually, he pulled away from her breasts, releasing her right nipple with a wet popping noise. He grinned at her, looking thoroughly pleased with himself.

"You have no idea how long I've wanted to do that to you."

She snorted derisively.

"Oh, go on with you, you liar."

"No, really Donna! Even before, when we were just friends, I couldn't very well deny that you were beautiful, that I found you attractive."

Suddenly feeling self-conscious, Donna sat up and pulled her knees to her chest, wrapping her arms around them.

"Stop it, Doctor. You don't have to do that, you don't have to say those things. I know I'm well past my sell-by date, and I was never much to look at anyway."

The Doctor growled.

"Donna Noble, you are beautiful and amazing and sexy, and if you won't believe me then I'll just have to show you!"

Gently pushing her back into a horizontal position, he resumed his oral investigation of her breasts, before moving gradually lower, kissing and licking his way down her abdomen. He lingered for a while at her navel, flicking his tongue into it before moving on. She shivered and tensed slightly when he gently nipped the sensitive skin near the crease of her groin. He stilled and raised his head.

"Are you alright? Do you want me to stop?"

Deliberately relaxing her muscles, Donna answered, "No. I'm fine, go ahead."

The Doctor looked doubtful.

"If you're sure…"

"I am. Please, Doctor, keep going."

Thus reassured, he continued his path down her right thigh until he reached her knee. Once there, he brought his hands into play, using his long, slender fingers to tickle the delicate skin at the backs of her knees until she writhed in frustration. Once he was confident that she was ready, the Doctor repositioned himself so that he was kneeling on the rug at Donna's feet with his hands delicately poised on her knees.

Donna gasped in a breath as the Doctor bent her knees and gently pushed her legs apart, exposing her heated core. No one had ever paid such avid attention to her needs, and she found it incredibly exciting. Murmuring soft reassurances, he trailed a fingertip along her inner thigh, before lightly stroking the crease of her groin.

Moving to lie on his stomach between her splayed legs, the Doctor used the fingers of his left hand to separate the folds of her labia, eliciting a delicious sound of anticipation from his lover. Smirking self-assuredly, he bent to his task.

Donna squeaked in surprise when her lover pinched her swollen clit, causing her to buck and writhe helplessly under his hands. Giving her no time to recover, he circled her entrance with a fingertip before slowly inserting the finger into her as she pulsated wildly around him. She moaned lowly as he withdrew his hand and then pushed it back into her, agonizingly slowly. She expected him to add another finger in the typical male belief that size was more important than skill, but he never did, continuing to thrust the single digit into her heat, changing his angle every so often to press against something inside her that made her hips buck wildly and her stomach muscles clench.

Finally- finally, he lowered his head and began to lick languidly at her clit whilst thrusting a little faster with his hand, and she was sent screaming, spiralling into orgasm.