[Here's the problem with contributing to what he knows full well is an inquiry designed to further flesh out Tseng's assessments of the resort: the fact that Tseng knows Rufus perhaps better than anyone living or dead, and so there's really no point in being selective about what he says or doesn't say. Tseng will read the unspoken implications as clearly as if he hadn't tried to leave them between the lines.

What remains, then, are two options: to deny him categorically, or to own the implications altogether. One would make him feel better. The other is the correct option.]

I had a drink from the floating bar. During the fireworks show. Gin, ginger beer, lime, raspberry. Edible flowers.

[Step one: identification. It might've been any one of the elements of the drink that carried the drug, or it might have been the byproduct of combining them. He keeps his expression carefully schooled, and knows that Tseng won't miss the fact that he'd accepted a brightly-colored cocktail, the sort he's not been caught dead drinking in public in years — a nostalgic product of a distant time.

He sips his whiskey. Fits together the next step in his thoughts.]

Symptoms...nothing physical. It impacted the psychological and induced a sense of intolerable isolation.

[An induced sense of isolation is perfectly clinical and serviceable. It doesn't sidestep the underlying implication, I felt lonely.]

So. An aphrodisiac variant. Compelled companionship, but targeted toward the psychological rather than the physical.