Poropo looked around the crowd surrounding the young boy Luca and felt uneasy - if any part of Giuliano's plan failed then Luca and the onlookers would know they have been lied to this whole time. One of the parts of Giuliano's complex plan involved Poropo distracting a certain number of people at a time to lessen the load on Giuliano's spell-casting - if the silly monk were to fail then, "I would not be a kind monk..." mumbled Poropo to himself. The conflicted monk could not make himself pull out of a job and expect to feel kind doing so - Poropo's built status as the "Kind Monk" of Fairy Tail was on the line as much as Luca believing he was magically inclined.
"Oh my, look at Luca do that amazing thing with his hands! He is surely a prodigious magician, no?" Poropo was decided to go along with the plan set by Giuliano - to make sure all attention was on Luca, including Luca's attention. If anyone were to look long enough at the pampering father, they might feel suspicious - suspicion can quickly lead to questions and questions lead to the unraveling of Giuliano's complex web of lies. The monk had to be convincing in his own amusement as well, making sure to be enthralled while worrying about the future of Luca.
As the Kind Monk, Poropo could feel his kindness being challenged in a way he could not have thought possible until seeing Luca smile and pretend he was the most magical person in the world - Poropo believed this spoiled child would grow up to be harmed greatly by his father's lies, in turn harming others to feel whole again. If the truth did not come out soon enough, a monster could be born by Giuliano's inevitably imploding parenting.
Unfortunately, Poropo kept doing his job well - when the party was complete, Luca and the crowd further believed Luca was a genius wizard for his age. Giuliano was exhausted from performing the real magic, but not tired enough to forget rewarding the sick-feeling monk. Before leaving, clutching his chest in emotional pain, Poropo commented, "May the Iron Deity bless Luca."
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