It is 'furry noise' combined with the sound of dying in the netfamous Roblox game. It means 'oh no' or you say it when something sad happens.
You can only decide it by knowing the rest of the monolog.
-so i met a nice girl yesterday
-Oh yeah?
-but it turned out that she wasn't into furrys.. I can't find a real relationship tho, maaan
- Well, owoof man. You'll find somebody one day bro. Don't worry
Boys who enjoy yaoi (a genre in Japan that contains sexual and/or romantic relations between two men); literally translates to "rotten boy"; corresponding female : fujoshi