How they first met: Mira had decided to travel to Hoenn for her pokémon journey after travelling through Sinnoh initially. She lost her first Gym Battle against Tate and Liza and, feeling a little sorry for herself, decided to explore a bit and train for her rematch. Being Mira, she ended up getting lost almost immediately once she strayed from the path. She asked her Alakazam to send out a psychic distress beacon which Tate picked up on, heading out to rescue her. While Mira was embarrassed at first about being rescued by the Gym Leader she had just lost against, her embarrassment quickly became admiration and quite a bit of a crush at Tate’s bravery in rescuing her and how kind he was about helping her out, even offering some tips to help her for her rematch. 
Where their first date was: Remembering the sweet and clever Gym Leader who had helped her out when she got lost, after beating the Hoenn League Mira headed back to Mossdeep and begged the twins to take her on as an apprentice. She was a skilled trainer, so they let her have a job as a Gym Trainer, despite her obvious crush. Well, obvious to Liza, Tate was oblivious. Eventually, after about three years of working at the Mossdeep Gym, Liza got tired of Mira making heart-eyes at her oblivious brother, so she clued Tate in to the situation. He felt so bad for not noticing his friend’s crush he asked her out the very next day (both to apologize for being dense and to figure out his own feelings for her). They visited a local botanical gardens and had a great time, deciding at the end to date officially.
When they had their first kiss: They actually kiss on their first date. While wandering in one of the greenhouses at the gardens they were visiting, Mira decided to directly ask Tate if he had feelings for her or not, since he had rushed into asking her out. When Tate admits that over the course of their date he has found himself more and more attracted to her, Mira squeals and then drags him behind a tree and goes in for a kiss. Tate is a surprised at her forwardness, but reciprocates (and is surprised when Mira admits that was her first kiss since she was so enthusiastic.)
Who cooks: Mira is not a very good cook, so Tate usually ends up cooking for their family. Liza and her family are often over as well and she and Tate love to cook together.
Who proposed: Tate. Despite Mira being the more enthusiastic of the couple, she’s also not very good at moving the relationship forward, so after a few years of dating, Tate decides to propose.
The dominant one: Mira, but only since she’s so enthusiastic and eager. Tate is certainly not passive, but Mira is more likely to initiate anything.
Their favorite pastime together: Despite her horrible sense of direction, Mira loves hiking and exploring nature, so she and Tate often like to use their free time to go on hikes, with Tate navigating. Otherwise, they went on a lot of museum (and similar locations) dates before getting married, and continue to enjoy doing so while married, often bringing the twins along for a weekend outing.
Who kissed who first: Mira kissed Tate.
Who is the flirt: Mira is quite the aggressive flirt, though Tate has his moments once they’ve been together for a while. 
Who is the romantic: While Mira is the more eager of the two, Tate tends to be more thoughtful and is often the one to plan dates and the like. He likes routines, so he and Mira have regular ‘date nights’, ‘couple’s nights’ and ‘movie nights’ that he enjoys planning.
Who wakes up first: Tate.
Who comforts who the most: Mira can be prone to getting worked up over a small inconvenience or irritation and need to be calmed down with help from her husband, while Tate tends to be a worrier and often needs his wife to remind him to take a deep breath and stop overthinking things too much. So really, it’s a tossup. 
The cuddler: Mira.
The big spoon: Tate.