It wouldn't have happened if Marjory hadn't left the Christmas party early. If Frank hadn't employed his wife in the same office as him and Gemma, it may have happened earlier.
Marjory was no fool, she'd seen the way Frank looked at Gemma. She would have stayed to keep an eye, but she had caught the winter bug that had gone through the office.
The low turn-out due to illness meant the party was over early. Frank stayed on to tidy the office. Gemma, with a sparkle in her eye to match the glittery make-up on her cheek, stayed to help.
On his return home, Frank left his clothes in a crumpled heap near the laundry bin and washed at the bathroom basin, taking care to wash the glittery make-up off his face. Then went to bed.
In the morning, Frank had some sobering up to do.
Marjory had recovered enough to get her house in order,
'You bastard, Frank.'
She was holding up his trousers. Frank had never been in this much trouble before, for failing to put them in the laundry bin. Then he saw that either side of the zipper were shimmering patches of glitter.