Everything so far was all part of the plan to help Serena on her path to Auristics. The trust exercise forced her to rely on other none visual ques that would prove invaluable later on as she was made to deliberately concentrate and focus. And before he would allow her to use Djed, and attempt to delve into this arcanic art he had to be absolutely certain she was ready.
When he asked Serena to open her mouth she had, he liked how she gave him a sultry smile. Any other time he'd succumb to that dirty thought that loomed in the back of his mind. But not right now, he was serious because he had to be. Magic wasn't a game, teaching her would tricky enough.
I want you to concentrate, focus for me darling
He plucked something from the bowl, it was a strawberry.
Which he would dance under her nose so she could smell the aroma of the fruit before delivering it to her palat. When he was finished teasing, he would place the strawberry in her expecting mouth, so that she may savor the succulent pop of flavor and the cool refreshment of the flowing juices. Maduro would indulge his sweet, with a few more, each time he did the same routine until she caught on.
Tell me beautiful how many things did you encounter with those berries ?
He was hoping she would name things like the texture, the aroma, the flavor, but ultimately the goal was to have Serena understand that something as simple as a berry had many elements that made it a strawberry.
This was key to understanding Auristics, deciphering minor elements within the big picture.