9 parts Ongoing MatureTwo weeks in Colorado is what it takes to start it all, igniting a a spark between the two. Two weeks of unintentional flirting, enjoying each other's company, and spending time together as a family is all it takes for feelings to start surfacing.
Katsuki and Izuku's daughters are best friends, and after they see how much fun they had together on their vacation, they are desperate to set their dads up. They keep making excuse after excuse to get them in the same room, and once Katsuki and Izuku catch on, they agree to go out one night just to get their kids off their backs.
As it turned out, their daughters were on to something because they both had a great night, realizing they had more in common than they thought and somehow got along great. When the night ended, they weren't sure where to go from there.
Their daughters were best friends. No matter what happened, they wanted to protect that. Even then, they decide a few more nights of getting to know each other can't hurt, right?