A good knot for restraining someone.
I am not asking because I plan to engage in BDSM, I'm asking because I'm doing research for a fanfiction, and I genuinely cannot find a good answer elsewhere. Figured I'd ask the experts.
For some context: I am writing a scene where one character (B) got kidnapped by another (A), and is now bound to a chair while being interrogated. However, character B notices that the birds are not as uncomfortable as they could've been, and uses that as evidence to suggest that character A actually likes character B (They're supposed to hate each other, long story).
Character B's arms are bound to the armrests of the chair at the wrists. I need a knot that's both sturdy and non painful in this context (though not necessarily comfortable). Ideally, it would be a kind of knot that, at most, military personnel would learn on the job, and at least, the average person would be able to do with light research. At this point in the story, character A does not care enough about character B to go out of their way to look into niche/obscure types of knots just to make them more comfortable, but if given the opportunity, they will choose one that is less harmful.