Rule number one for spying on Aral Vorkosigan, Illyan discovers, is: do not ever let him get drunk.
The second rule follows from there: if he does get drunk, get him somewhere private. Quickly.
The third rule is a hop, skip, and a jump of logic from there: if you cannot get him somewhere private, get him to stop talking by any means necessary. Illyan's job is to make sure Vorkosigan doesn't incriminate himself. He's under Imperial order to do so and to use his discretion in choice of methods, or so he tells Negri when Negri asks him what in three living hells possessed him to kiss Aral Vorkosigan.
"It was kiss him, or let him be killed for treason," Illyan says. "I chose the former."
"Vorkosigan's been talking revolution in his cups since he first discovered alcohol," Negri says. "It's expected and everyone is used to it. What they are not used to is him having sex with an ImpSec officer on a table in a dive bar in the caravanserai."
Illyan does not quite shrug. "That was not in my briefing materials, sir. I will keep it in mind for the future."
It becomes rule number four.