Gardevoir has a 50% chance of being male and Machamp has a 25% chance of being female. Hopefully you know that.
On to the characters themselves. Theodore (Theo for short) is a smug, pompous Gardevoir. His demeanor is mostly just an act to cover up his insecurities and all that good stuff. Reya is tough and stern, but it can be easy to point out her insecurities. Theo annoys Reya and when they first meet, they basically play a game of “who can point out the most insecurities in the other.”
Will their relationship get better? Perhaps.
