If they had noticed the change in action in themselves, in all likelihood, they would already have a prepared answer. But if they reacted flustered, it would mean that they hadn't thought much about it and would be more likely to be innocent in the matter. This could be the case if the phone of said partner recently got a new case that made it more difficult to pick up while it was face up, so they had gotten into the habit of placing it face down now for easier access. They might have made this choice subconsciously and never really once thought about it.
Webnovel
the author is speaking from experience
If they had noticed the change in action in themselves, in all likelihood, they would already have a prepared answer. But if they reacted flustered, it would mean that they hadn't thought much about it and would be more likely to be innocent in the matter. This could be the case if the phone of said partner recently got a new case that made it more difficult to pick up while it was face up, so they had gotten into the habit of placing it face down now for easier access. They might have made this choice subconsciously and never really once thought about it.
Dimensional Descent
Fantasy · Awespec