From the very start Aria-shachou hadn't been afraid of Shirogane. If asked, Akari would cite that as proof of Aria-shachou's intelligence.

She laughed a little as she set Shirogane's cup of tea in front of him. "Aria-shachou really likes Shirogane, doesn't he?"

Aria-shachou, who had flopped onto his back when Shirogane pushed him sat back up with a cheerful, 'puinya' as if responding to Akari before attempting to burrow under Shirogane's arm. Because clearly that is the best idea when one is a really plump cat.