One thing I noticed about XY047 (the episode when Serena sees Tripokalons and meets Pancham), Chespin seems unusually involved with the whole episode.
Chespin let’s himself out because he wants to be brushed by Bonnie and Serena along with Fennekin.
When the group is watching Aria and the other performers on stage, Chespin let’s himself out of his Pokeball without permission to watch too.
Chespin starts to do his own little Pokemon performance after watching the Tripokalon show, a reflection of his enthusiasm.
Chespin is the Pokemon to (negatively) engage Pancham the most.
In retrospect, a lot of Chespin’s actions in previous episode so far lend himself into favoring Serena’s sphere of influence:
Especially since Chespin loves Serena’s macarons.
Serena is the one in the group who has invested herself into Chespin and Clemont’s relationship the most.
Chespin’s attraction to Aria’s then-Fennkin now-Braixen causes subsequent friction between him and Serena’s Fennekin.
Serena’s potential growing strife with Chespin.
Collating all these instances of Serena’s interaction and influence on Chespin is leading me to believe that a more substantive dynamic between Serena and Chespin is very possible. To what end I’m as not exactly sure. But I have inklings of suspicions that perhaps Chespin may want to get involved with Tripokalons in the future, noted by how the latest episode showed Chespin as very enthralled by them.
What effect this would have on Serena and Clemont’s friendship, I’m not sure as well. However, it would be really compelling if Serena and Clemont end up both having an equally vested interest in Chespin which could be one of many potential avenues for the two’s friendship to evolve.