I was not the only alien infiltrating the sanctum. While Chatterton and his brave band steered clear of the young people, Joseph Grady did not. He encamped in a corner, behind the widespread pages of his newspaper, and they ignored him. He offered nothing; neither did Derek, who seemed to be of the persuasion that we were amply rewarded by his very presence among us. Abby, on the other hand, acknowledged the pleasure of Valerie’s company by bringing her things: a silver miniature of a llama, a string of amber worry beads. Once it was an ivory netsuke of a mouse whose charm, not unlike her own, induced breathlessness.

Tonight they sit on the grungy rug, the two visitors like steadfast planetoids around the star that holds them in place. Derek sprawls against a cushion. Beside him is Valerie, her bare legs airborne, hinged at the knees and crossed at the ankles, perpendicular to her prone body. Facing her is Abby, kneeling in an attitude close to supplication. Between them is a chessboard. They’re playing checkers, more or less. She studies the pieces, nibbling the petals of a bright chrysanthemum, another gift from Abby. Trying not to be obvious, he tilts his torso to run his feverish eyes inside her open-throated blouse, just as I am doing. Derek, of course, has all the best of it. While Abby’s contortions and mine compete for a less impeded vista, Derek is running his hand up and down her leg, rounded knee to slim ankle, again and again, slowly, maddeningly.

I can’t stand it; I try to concentrate on the game, not easy because I’ve never found much stimulation in checkers, although no less an authority than Edgar Allen Poe had written something like “the higher powers of the reflective intellect are more decidedly and more usefully tasked by the unostentatious game of draughts than by all the elaborate frivolity of chess.” But I doubt if Poe’s concentration was ever contested by a spectator’s reaching out to cop a cheap feel off one of the players.

Valerie’s leg shot out reflexively. “Cut it out, quit it,” she said.

“Cut out what?” Derek asked with a kind of sly innocence. His grin was close to a hyena’s.

“You know what.” A film covered her eyes, as if they had been daubed with a damp cloth, and her mouth trembled ever so slightly. She rolled over and sat up, cradled a leg in her lap and examined it. On the brown calf were two scarlet little half moons like parentheses where his nails had bitten into her flesh.

Abby leaned forward, attentively silent and with a hound’s devotion. A dog-smirk of embarrassment for his friend’s savagery shadowed his lips.

The light twist of my mouth must have telegraphed my censure to Derek.

“What?” he asked.

“You,” I said, “you make me sick.”

“Stay out of this.”