Who felt romantic feelings first?
What are their parallels, whether in their personalities or their histories?
Heya, Mytho! Funny thing; the first thing I did when I saw you show up in my ask box was open your blog to see if you had reblogged this prompt list. I would love to send you one or two questions from it if you're in the mood! Severia x Nero was one of the first wolships I personally became a fan of!
As for the questions, it was Tataru who felt romantic feelings first. It was an idle thing at first; he was just a handsome new Scion, and Tataru tried flirting with him once or twice. Johnny didn't really notice she was flirting and was crushing on Minfilia at the time, so nothing came of it.
They became extremely close platonically over the course of of Heavensward, and by the end of the Four Lords quest in Stormblood, neither of them would hesitate in naming the other as their best friend. Tataru, out of respect for his lingering feelings about Minfilia, did not press romantic matters again with him until post-SHB. I wouldn't say she was actually "in love" with him until a short time after they started dating, since beforehand she had been content just being friends. Her feelings did quickly turn to the same shade and magnitude as Johnny's, lucky for them both.
Despite their vastly different character archetypes, the two do have a few notable parallels! They were both poor kids from Thanalan, and both were born under Nald'thal's guardianship, which is appropriate given the Traders are the patron of both merchants and black mages. They were born less than two weeks apart as well.
They both have an affinity for cute animals (something they share with their daughter Beruru as well). Perhaps their most obvious parallel though is that in both of their cases, their most recognizable character trait is found on the top of their head!
Thanks for the questions! It was fun thinking about both of them, and it helped me understand them better.