The use of her ass. [15 denarii]

You pull Tanis up by one hand and lead her over to a couch, without saying a word. She quirks an eyebrow at you but follows your command, and complies when you push her over so that she is bent at the waist. When you pick up a small jug of olive oil, she chuckles. "Men. You always want the most exotic services for special occasions."

"Well...it is my birthday," you reply with a chuckle. Carefully, you massage the oil over your cock and then pour a dribble down her lower back, using your fingers to massage it into her dark, tight asshole. You play with her clit and labia for a few minutes as your cock stiffens, and she squirms in apparent delight beneath your touch. "Hold yourself open for me," you tell her huskily.

Tanis smiles tauntingly at you, then leans forward and reaches back to pull her ass apart and allow you access. Pressing your cockhead to her ass, you slowly make your way inside. "Mmmmmmph. Yes...there it is," she whispers. She seems to be focused on processing the sensations, but doesn't seem to dislike it. After a second, you're thoroughly lodged inside her. Her sphincter is wonderfully tight; Tanis is breathing steadily, rhythmically, trying to make sure she's relaxed enough to take you. "Go slow, Lord Gaius," she says. Then she glances back at you, smirking slightly over her shoulder. "But not too slow. I can take it."

You smile back at her and begin to pump - slowly at first, then with increasing ****. Tanis lets out a deep groan, and you echo her as you slide your cock in and out of her tight hole. "So full," she mutters - not necessarily to you.

"So tight," you reply anyway, lost in a haze of ecstasy. You pick up your pace as you feel your climax approaching making Tanis's buttocks shudder with the impact of each stroke and her breasts bounce distractingly beneath her. "I'm...going...to...ahhhhhhhhhh." You release your seed inside her as both of you moan, your cock pulsing with pleasure and biological need as you flood her ass with your cum.

You lie entangled for a few minutes, then Tanis slowly pulls herself away from (and off of) you. "Well done, Gaius," she says with a little smile. "I'll be - phew - walking a little strangely the rest of the day." She closes the distance and plants a kiss on your lips, giving your cock - which is now quite tender - a last, slightly aggressive squeeze with her hand as she does so. "Happy birthday again, Lord. And with that - since I doubt there is more in either of your purses that you can spare right now - I had best be off." With a little wink, she snatches up your coin purse, takes her payment from it, and tosses it back (considerably lighter) to you. "Here you are. Buy yourself a nice birthday present. Not one as nice as me, of course." She dresses quickly as you regain your breath on the couch. "And should you ever wish to employ me again, well...you can find me at Vita's Place, not far from the Forum. Ask around and it shall be pointed out to you." She crosses back to you on the couch and bends down to look into your eyes (conveniently giving you a wonderful look down her dress). "I shall remember you," she promises, a bit performatively. She takes the weight of it out by grinning and biting your ear playfully, then sashays out of your room.

Catching your breath, you stretch, cross to the balcony and pull back the curtain, stepping out onto the roof of your home's first story. Below you, Rome is already abuzz. Your home stands on the slopes of one the Quirinal Hill; not in the center of town by any means, but it's still a part of the old city. You idly splash some water on your face from a jug nearby to clear your eyes, and consider the day before you. As a nobleman, even a minor one, in your majority, you don't have many urgent duties pressing on you; your family fortune is enough to sustain your day-to-day living, even if you would like to have more coin for lavish expenses, like your birthday party. But you're a young man of ambition, and in your heart you hope to climb to the very top of Rome's social order.

The question is...where to begin that step.