The specific rendering appears to be a result of character encoding issues (mojibake) where non-ASCII characters (likely Korean or Japanese) are incorrectly displayed. In its intended form:
The phrase originates from Japanese (あわわ) to signify a stuttering sound made when someone is speechless or in a state of frantic confusion.
Characters in visual novels or RPGs often use "awawawa" in text bubbles when caught off guard. Shirakami Fubuki Quotes - Azur Lane Wiki
It has become a hallmark "catchphrase" or reaction for various Virtual YouTubers (VTubers), used both as a verbal tic during streams and a text-based emote in chat.
It corresponds to 아와와와 (awawawa) , which mirrors the Japanese usage for surprise or panic.
It is frequently seen in TikTok edits involving anime characters or VTubers reacting to unexpected events. Example Usage in Media