There was a story I read similar to this, and it was one chapter long in a compilation of oneshots. Does that sound like the one you're looking for? I can't recall the name right now, but if I remember, I'll try posting it here!
yeah that would be great!! :)
So I reposted your question with the details I remembered. Kathy and Empress.Yaoi. both gave me the answer. I hope this is the one you're looking for!
http://www.mangago.zone/read-manga/tsuki_ni_hoero/tr/98823/page/116/
You are amazing!!!! That's it!! thanks so much!
I found this comment posted and would like to read it again as well, no luck finding so any help would be great!
"American man sees his ex lover (Japanese guy) at a business gathering in america and finds out he's getting engaged to a clients daughter....then the american guy flips out, he gets jealous and they...well yah know?
I really wanna reread this except I forgot the title >< and the characters names...I was to focused on the story and plot instead. - "