Watching "Shoshimin: How to Become Ordinary" episode 2 and honestly much like Monogatari and Ishura, it is a showing that going back in a rewatch gives you a different look for this series.
First being the conversation with Kengo before the little mystery starts. Kengo mentions how much Kobato. Very much the type of person that acts the part and going along with just to change. It makes you wonder what could possibly cause him to change.
The whole hot coco mystery was less about the mystery, but more so the characterization of Kobato. The first point it showcases his curiosity about how did Kengo create the 3 cups of hot chocolate with no spills. Tbh it more showcases how meddling Kobato can be. As a viewer for the first time, you are left wondering, why are we solving this mystery when we can just ask Kengo? But this is Kobato's nature of being a smart ass and having to know the answer without getting help. It's an ego thing.
The last part of the episode dwells on Kobato & Osanai's farewell conversation. More so the meddling type of person is who Kobato is. It brings up two questions. Why does Kobato want to change? The only clue is that he says he is done playing detective. More and more giving the impression he tries to solve other perople's problems as a narcissist.