Last time, on A Pokémon Trainer Is You:

What do you do on route 22?
– Train with Nancy, the Negator.
– Perform an ecological survey.

Once Nancy is recovered from her battle, you decide to do an hour or so of basic training – exercises, attack drills, dodging Scallion’s Vine Whip attacks, that sort of thing.  Everything you’ve seen from Nancy so far suggests that she’s a very gentle and mild-mannered Pokémon, but she takes battle and training very seriously, and celebrates her successes with gusto.  You suppose that shouldn’t be surprising, for a Pokémon who approached and challenged a human trainer.  It’ll take time for her to reach her full potential, obviously, but you can see some improvement even in the short time you have to spend.  Once Nancy starts to tire of training, you take another look at the relatively meagre information your Pokédex has on Minun.  The key words and phrases all seem to be about teamwork.  In their native Hoenn, Minun often live closely with a sister species, Plusle, each amplifying the other’s electrical powers, but they can apparently team up with just about any Pokémon, given time to establish a bond.  The Pokédex is considerably less clear about how a trainer might go about doing this, or exactly what advantages might accrue from it.  One thing is clear, though – Minun love to cheer for their friends in battles.  You try this out, getting Scallion to perform a couple of quick, very basic training exercises, and find that he is inexplicably faster and more accurate with Nancy’s active encouragement.  Hmm.