Thanks to anon D and an anon for reviewing.
Disclaimer: I don't own Hetalia.
Belkraine: Wedding Day
Bella and Kat were playing together. The two little girls were sitting in front of the TV while playing with the dolls, but they weren't exactly paying attention to the TV, at least until they saw that there was a wedding in the movie.
"Wow," Kat said. "So pretty."
"Yeah," Bella said. "I can't wait to be old enough to have a wedding too."
"Who do you want to get married to?"
"I don't know. Ooh! We should make a promise!"
"What promise?"
"That we'll get married on the same day. It'll be so fun."
Kat giggled.
"Okay," she said.
…
Bella leaned over to whisper something in Katyusha's ear.
"Do you remember that promise we made as kids?" Bella whispered.
Katyusha nodded, a small smile on her face.
"I'm actually surprised by how easy it was to keep that," she whispered back, before she kissed Bella.
There was a cheer from the guests, and the two smiled into the kiss. The promise had been easy to keep. However, never in their wildest dreams did they imagine that when they got married on the same day, it would be to each other.
Strange how fate worked.
The prompt is: 'Your OTP were best friends as children and promised each other that they would get married on the same day, which was an easy requirement to fulfil when they were older because they married each other.'