The Annoying Dog debuted in Toby Fox's role-playing game Undertale, released in 2015, as a recurring white dog widely read as the creator's in-game avatar. It appears without warning, absorbs key items, and leaves heroes empty-handed, building its reputation as a lovable troll. Clips of its barking and its mischief spread through Tumblr, YouTube and gaming forums after launch, then into general meme edits far beyond the fandom. Its persistence comes from that perfect mix of cute appearance, total uselessness and impeccably timed disruption.