Spark's Boxers --but spark wears super skinny jeans. If he wore loose boxers they'd show/roll up/get ensnared in things. He probably wears sports briefs or boxer briefs<< great now I know what underwear Spark wears?
Oh my goodness. the father is a DITTO! And is the best parent ever! THE FEELS! I didn't realize until the end it was a ditto! At first I was like, what is up with all these other Pokemon are they his friends?