(Inspired by watching the greatest movie of all time, Love Actually, the other day.)
Alan and Emma are a middle-aged married couple, and though Emma is a goddess Alan is nevertheless having a midlife crisis. For the past few months he’s been noticing his much-younger secretary, Miam who is frankly a skank but that’s not the point.
Anyway, on 2 December, at the office Christmas party, Mia waits for a moment in which no one else is around, approaches Alan with a piece of mistletoe in hand, and asks for a holiday kiss. When he gives her a peck on the cheek, she pouts, and then grabs him and sticks her tongue down his throat, saying he can have more at will. Alan does not resist the tongue-down-the throat, but he does not stick his tongue down hers in return.
Mia continues to make her sexual availability known to Alan, though she remains discreet about it. On 9 December, at lunch, he notices her looking at a particular piece of expensive jewelry in a catalogue and makes note of it. Mia invites him out for drinks that evening, and he agrees to go; he calls his wife and tells her he has to have drinks with a client. The post-work-drinking is filled with salacious conversation. As Alan and Mia are leaving the bar, they walk under mistletoe, but to his surprise she does not kiss him. When he asks why, she says that she is tired of doing all the pursuing. If he wants another kiss he will have to initiate it, After a moment’s thought, he grabs her and kisses her. After a few moments of making out, she tells that if he wants any more, she will need a token of his affection. It needn’t be expensive; a $10 paperback book of love poetry will do it. They part on that note.
Nothing more happens for a while, as Alan has to leave town on business. While he is out of town, on 16 December, he buys a copy of Browning’s Sonnets from the Porteguese for Mia, paying exactly $10. When he returns to town, on the morning of 18 December, he gives Mia the book, inspiring her to kiss him again, manipulate him manually to orgasm, and promise him something better that night.
That afternoon, Alan and Emma go to the mall to finish their Christmas shopping. Alan is distracted the entire time for obvious reasons. He buys an expensive gold necklace for Mia, concealing it from Emma for reasons left as an exercise for the reader. When he returns to work, before he can even tell her that he’s bought a present for her, she goes into his office, closes and locks the door, and tells him that she is so excited she cannot wait, and thus gives him a blowjob. He reciprocates orally as well.
That night they engage in coitus.
In this scenario, when did Alan FIRST cheat?