Sorry if I'm getting in ahead of the rest of you, but where I live (downunder) it will soon be bedtime for me. I've discovered that when I log in again in the morning that all the discussion has been had, all the interesting quotes have been found, and all the insightful commentary has been made. So I'll get in early for the discussions of 16 - 20 with this from ch. 19:
“Hey. Ellery. We got a situation downstairs. It’s Wilson and he showed up and he’s drunk and he’s mad. Bill has got him at the bar but things are getting ugly.” The blond youth was shaking.
“Did he show a gun?”
“Don’t know, don’t think so Ellery.” Gene’s face was white with tension.
Ellery turned and gave Ennis a long look, and then took out his gun, checking it as he did. “Ennis can you keep Pete up here outta trouble?”
Ennis nodded, a lump rising in his throat. He was genuinely fearful for Ellery. The deputy paused and glanced over his shoulder at Gene. "Go down and tell Bill I’ll be right down, but make sure Wilson don’t hear ya.”
“Sure enough.” The blond head disappeared as he clattered back down the way he came. Pete sat, inert as a stone, staring at nothing, but Ennis wasn’t paying attention to Pete at the moment. His eyes filled with sudden moisture, tears welling up.
“Ennis,” Ellery said, his voice pitched low.
“Uh, yeah, I’ll look after Pete.”
“Ennis.” He took a step toward Ennis, reholstering his gun and holding out a hand, grasping his elbow.
“I said okay.”
“You gonna be all right?”
Ennis looked at Ellery searchingly, then, his chest tight with an unspeakable, horrible pain. “Jes – be careful. I don’t want nothin to happen to ya.”
Ellery smiled, a hint of that mischief returning. “Don’t worry, we got a getaway car, remember?”
Is this the moment we know for sure that Ennis cares about Ellery far more than 'just friends' would imply? The situation parallels a very similar situation much later in the second book when Ellery is about to set out to Texas to find Jack's killer, and Ennis is similarly fearful for Ellery and virtually tells him not to go because he couldn't bear the fact of Ellery getting killed, and he again would lose the man he loves.
I also like the sensitivity that Ellery shows at this moment, aware that Ennis is worried about what could happen to him, and taking the trouble to reassure him. Characteristically, he does it with an offhand quip about 'a getaway car'. Note also the use of 'we' in that line, reinforcing the idea that they are partners in this tense situation.